In ‘Renewable energy’ Category

monitoring_guide_phone

Knowledge is power – Energy monitoring guide

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Need help getting the upper hand on your electricity bills or checking that your solar system is working? You should consider an energy monitoring system, says James Martin from Solar Choice.

DO YOU have a clear picture of what’s drawing electricity in your home right now? If you’re like most Australians, you probably don’t.

READ MORE »

Historically, this hasn’t been an issue because electricity bills weren’t a major concern for most households and, in any case, the number of devices was probably small. But these days electricity prices are high and there are likely to be more electricity-consuming devices plugged into the walls of any given home than the occupants can think of off the top of their heads.

Many Australians have turned to solar panels to help them fight rising prices. Rooftop solar is now affordable and commonplace — the Hills Hoist of the 21st century.

However, comparatively low solar feed-in tariffs in most places mean that solar homes have less incentive to send solar electricity into the grid and more incentive to use it directly. Despite this fact, many (if not most) solar system owners would be at a loss if you asked them how much energy their system produced yesterday, never mind the proportion that they managed to self-consume.

Solar systems have even failed without the homeowner realising until they received their next bill. So monitoring is important!

Types of energy monitoring and management systems
Thankfully, there’s a growing number of products on the market that shed light on household energy consumption and solar generation. These devices take a range of approaches and offer a range of functions, but can generally be classed as either monitoring systems or management systems.

As the name implies, a monitoring system enables the user to ‘see’ what’s happening with their electricity, usually via an app or web-based portal, whereas a management system lets them not only observe but also ‘reach in’ and control which devices switch on at what times.

In reality, the line between the two is becoming increasingly blurred as platforms that once offered only monitoring get upgraded to let them do more.

Monitoring and management systems can be lumped into roughly five categories based on how they are physically installed in the home.

Read the full article in ReNew 141.

IMG_1790

Towards grid independence

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

What happens when a home with very low electricity use adds a battery? Terry Teoh describes his home’s interesting results.

OUR house is an Edwardian three-bedroom brick home renovated in 2010 along sustainable design lines. With two occupants, our house achieves a very low average electricity consumption of 2.4 kWh/day, though note that gas is (currently) used for space heating, cooking and boosting of solar hot water.

READ MORE »

We installed a 5 kW solar PV system in December 2016. With the array oriented east and west, the seasonal difference in energy production is accentuated compared to a north-facing array: our system produces on average 26 kWh/day in summer and 7 kWh/day in winter.

In April 2017, we added a 4 kWh Sonnen eco8 battery to our system to provide solar load shifting—storing solar energy produced during the day for use at night.

In the first two months of operation (to June 2017), our house has moved from 30% to 70% grid independence—i.e. 70% of our energy is now generated by our solar system.

Interestingly, that 70% is lower than we expected given a substantially oversized solar array and battery. It turns out that our standby energy usage is too low to be served by our inverter!

However, it’s still a good result and the battery has lifted solar self-consumption from 5% to 50% and paved the way for us to disconnect from the gas network and move to an all-electric, renewably powered household.

Motivations
Our motivations for installing a battery system included a desire to maximise solar self-consumption and grid independence. The latter is not out of antipathy for energy companies or the grid. We want to stay connected to the grid.

The grid is good; it will just be used in a different way in the future to support a decentralised energy system where consumers will have more control over how they make, use, store and share energy.

Read the full article in ReNew 141.

Saltwater_Batteries

Saltwater batteries in use

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

When the old battery bank gave out, it was back to diesel for a time at this significant conservation site in the Mallee. But an innovative off-grid upgrade has changed that and led to a significant improvement over the old system, as Trust for Nature’s Chris Lindorff and Tiffany Inglis explain.

UP IN the Mallee, along the River Murray in far north-west Victoria, lies Neds Corner Station, a former sheep property now being restored as a significant natural habitat by the not-for-profit Trust for Nature.

READ MORE »

With an extreme climate—temperatures soar close to 50 °C in summer and frosts occur in winter—and no grid connection, this 30,000 hectare (300 km2) property presents challenges not only for habitat restoration, but also for the off-grid energy system needed to support the on-site rangers and visitors.

Purchased by conservation organisation Trust for Nature in 2002, the site is now home to two rangers and up to 30 visitors at a time: researchers and students studying the flora and fauna; bird groups conducting site surveys; works crews working on neighbouring public land; volunteers assisting with site restoration tasks such as reducing rabbit numbers, replanting local species and installing fences to keep out foxes; and the occasional corporate days and camping trips.

The site includes a homestead, shearer’s huts (used as accommodation), kitchens and conference/workshop rooms, with associated energy needs for heating/cooling, lighting, water pumping, refrigeration and gas cooking.

Energy system, take 1
When the property was first bought by Trust for Nature, the site ran solely on a diesel generator. Then, in 2012, philanthropic donations enabled the installation of a solar power system with a lead-acid battery bank. The system was designed to cater for an average of 25 kWh/day energy use, with a 25 kVA diesel generator as backup.

Over the following years, however, more people came to Neds Corner and energy demand increased, which led to the generator running more often than not.

Frequent, heavy cycling of the flooded lead-acid battery bank meant it performed poorly and reduced its lifespan. Following the failure of multiple battery cells in 2016, the battery bank was disconnected and the diesel generator again became the sole source of electricity.

Read the full article in ReNew 141.

Travis_Pic

ATA member profile: Spreading the word on sustainability

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Long-time convenor of the ATA’s Perth branch, Travis Hargreaves tells Anna Cumming about his experiences in the retail solar sector and his real passion—educating people on sustainability and equipping them with the knowledge to continue the conversation.

ORIGINALLY from Melbourne, Travis Hargreaves took off around Australia on his motorbike when he was 20. “I went here, there and everywhere, then I ended up in Perth and met my partner, and the rest is history.” Travis has been in Perth ever since and is a stalwart of the sustainability movement there.

READ MORE »

“I always had an interest in sustainability and the environment,” says Travis.

Ten years ago he decided to get proactive and do some study in renewable energy; the TAFE in Perth didn’t offer a dedicated course, so instead, Travis was one of just two students that year who undertook a Diploma in Electrotechnology, which covered renewable energy as one of its four subject areas.

At the same time, he started up his first solar business: “The market was small at the time. I provided solar system design, sales and installation services for three solar retailers,” he explains. In 2010 he set up a solar retailer that services Perth and southern WA with solar and battery storage system design and installation.

Travis has far more on his plate than simply running his business though. When the ATA’s Perth branch was set up, Travis got involved and was swiftly asked to become the convenor, a role he’s held since 2009.

Through the activities of the ATA branch, Travis has become a sought-after speaker on sustainability and it’s this educational role that inspires him the most.

“Consumers are wanting to get past the talking and have the information to take action,” he says. “I started talking about energy efficiency and the importance of making those changes before investing in solar. Then I developed presentations on the basics of solar panels and battery storage, then about three years ago I started promoting electric vehicles, and now vehicle-to-grid technology.”

“I like my audience to leave inspired but also frustrated and wanting to push for change; I try to give them the knowledge to continue the conversation. Rather than bombarding them with technical information, I provide them with arguments for why we should be heading down this path so they can have conversations with their neighbours and explain the benefits—to living costs, local job creation and, of course, the environment.”



Lobbying for renewables and the jobs that go with it at the Rally for Renewables in Perth in 2014.


Travis has been involved with several other environmental advocacy groups. He was the WA branch president of the Australian Solar Council in 2014 and 2015, and instrumental in the 2014 Rally for Renewables campaign in Perth which brought together a host of organisations to lobby for legislation favouring renewable energy.

He’s also proud of a successful joint campaign to protest and reverse the WA state government’s decision to remove the solar feed-in tariff in 2013.

While Tony Abbott was prime minister, local representatives from both the Australian Solar Council and Clean Energy Council met with Liberal senators in WA to discuss local renewable energy and the potential benefits to the community.

It was useful education for Travis. “I think we were successful to a certain extent, but I also became aware of how the politics around renewable energy worked. They understood, but were toeing the party line.”

Travis is quietly keen to keep on pushing for change. “I got involved with the ATA because of its independent voice and its mission to provide information to the community. That’s what I continue to do today—use my knowledge to educate and influence people and inspire them to take action.”

This member profile is published in Renew 141. Buy your copy here.

MaxBoegl_windwater

News: Innovative water battery

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Pumped hydroelectric storage to help maintain grid stability is not a new approach for the energy industry—indeed, it was first used in the USA in 1930. However, German wind turbine manufacturer Max Bögl Wind AG has introduced an innovative twist, which they showcased at the Energy Storage North America (ESNA) fair in San Diego in August. The ‘water battery’ combines renewable power generation with a modern pumped-storage power plant to be used in periods of high demand. The pumped-storage power plant is available in three performance classes (16, 24 or 32 MW) and can switch between production and storage within 30 seconds.

READ MORE »

The first project to use the technology is being developed in Stuttgart, Germany. It comprises a windfarm of four turbines, each of which have tower bases with in-built water storage capacity of 70 MWh. These are connected to a hydroelectric power station with 16 MW installed capacity and a lower reservoir in the valley 200 m below.
www.bit.ly/MBWAGWB

Feature image: This windfarm in Stuttgart, Germany, is using wind turbines combined with pumped hydro for energy storage, with water stored at the base of the turbines! Image: courtesy Solar Consulting

alliance whole group at congress_600px wide

Energy justice for First Nations communities

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Aboriginal representatives at the Community Energy Congress have formed an alliance to achieve affordable renewable energy for First Nations communities. Kate Greenwood writes that the ATA is honoured to be part of this process.

ONE OF the highlights of the second Community Energy Congress, held in Melbourne in February this year, was hearing the voices of 13 Aboriginal leaders sharing their personal and powerful stories of what energy justice means to their communities. For some, it is literally a matter of whether they can remain on their ancestral land.

READ MORE »

The Aboriginal leaders took to the stage alongside Melina Laboucan-Massimo and Chief Gordon Planes from Canada. In contrast to the enormous energy security challenges faced by Australia’s First Nations communities, in Canada 50% of community energy is owned by First Nations people. Having delegates from Canada inspired everybody and enabled participants to realise the transformational possibilities of community energy.

In special breakout sessions of the congress, those communities negatively affected by resource extraction, dependence on fossil fuels and climate change met to talk about how renewable energy can be part of a story of hope and a catalyst for change, renewing and regenerating their communities. While the bigger goal for Aboriginal communities is self-determination and sustainable nationhood, renewable energy is a means to get there.

One of the most exciting moments of the congress, on day two, was the launch of the First Nations Renewable Energy Alliance, formed by Aboriginal representatives in attendance.

Fred Hooper of the Murriwarri Nation highlighted the massive change of direction. “We go to government all the time,” he said. “And yet for 200 years the government has been putting us down. This congress has opened our eyes.” He said the power of people to galvanise and make an immediate impact was clear. “What this congress has given us is a chance to get people in one place and build something for us, in partnership with all of you in the audience today.”

Read the full article in ReNew 140.

IMG_3981 400px

Capital improvements: The path to all-electric

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Switching to electric appliances wasn’t really thought of as economically or environmentally beneficial 10 years ago when Ben Elliston’s household started their efficiency improvements, so theirs has been a gradual path to all-electric. By Robyn Deed.

You could call Ben Elliston’s household a ‘poster child’ for getting off gas, but that’s not how it began. Rather, when they started the process to improve the efficiency of their Canberra home 10 years ago, the family’s mindset was aligned with the message at that time that gas was a cheaper and relatively clean fuel, compared to grid electricity. Ten years on and several ‘face-palm-why-did-we do-that’ moments later, they are now enthusiastically all-electric, with their energy use, operating costs and greenhouse gas emissions all pleasingly reduced—and with some added advantages of their new electric appliances that they didn’t expect.

READ MORE »

Looking back, Ben says one of the biggest shifts has been in what a state-of-the-art electric appliance looks like. From the simple electric element appliances of the 80s (the coil cooktop, electric blow heaters and electric element tanks), many of the newer appliances offer not only lower running costs—over both gas and older electric units—but also safety and other benefits. Ben says, “There were lots of advantages we hadn’t anticipated when we shifted to electric appliances. For example, our induction cooktop has smarts to switch off if it senses that a pot is too hot and has run dry; our heat pump air conditioner is also much quieter than our old gas wall heater.”

The other major factor for Ben’s family is environmental. With the ACT now well on the way to 100% renewable electricity by 2020, Ben says, “In 2020, our household will be net zero emissions, which would not be possible if we were still using any gas appliances.”

Read the full article in ReNew 140This article is based on a talk given by Ben Elliston at the ATA’s Canberra branch meeting in April 2017 and an interview with Ben. Click here for slides from the talk.

Capture

Solar sizing: big returns

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Why it’s now advisable to ‘go big’ when installing a solar system, even if you don’t use much electricity: Andrew Reddaway presents the latest ATA modelling.

Many people ask us what size grid-connected solar system they should get. Traditionally, the ATA (ReNew’s publisher), has advised people to consider this carefully. If you primarily want to help the environment and cost is of little concern, it has always made sense to install as many panels as possible, as all their generation displaces electricity from dirty, centralised power plants. But most people have budgetary constraints, so their solar system needs to make economic sense as well as help the environment. To achieve this, we’ve previously recommended that people size a solar system based on their electricity consumption and maximise their other opportunities, such as energy efficiency. However, things have changed.

READ MORE »

Two big changes

1. Solar system prices

The last five years have seen significant price reductions, especially for larger solar systems. Prices vary with component quality and location, but on average a 5 kW solar system now costs around $6200 according to Solar Choice’s residential price benchmark data.

Let’s compare a 5 kW system to its smaller 2 kW cousin. To compare two different system sizes, the cost is presented in dollars per watt. Figure 1 reveals that since August 2012, the larger systems have halved in price, while the smaller ones have dropped by only a quarter.

Larger systems have always enjoyed economies of scale compared to smaller systems, because while the installer is on the roof it’s relatively easy for them to add more panels. One difference now is that the price of solar panels has fallen faster than other components. The industry has also become more familiar with larger systems, as they are now more frequently installed than small ones.

2. Feed-in tariffs

The Victorian government recently announced that solar feed-in tariffs will rise to 11.3 c/kWh from 1 July 2017, roughly double their previous level, and IPART has recently recommended a similar change in NSW. These changes are primarily due to wholesale electricity prices in the eastern states roughly doubling over the past year to around 10 c/kWh. We expect other states to follow suit, as feed-in tariffs below the wholesale electricity price are clearly unfair to people with solar. (In WA, a similar rise in wholesale rates hasn’t occurred, but prices might still rise due to the state government winding back its subsidy of electricity prices.)

What this means for solar system sizing

Given these changes, if you’re planning a solar system, is it worth it to upsize from, say, 2 kW to 5 kW?

The extra panels will be relatively cheap but more of their generation will be exported, which doesn’t help the economics.For example, depending on household consumption, a solar system rated at 5 kW might export 80% of its generation. Electricity exported to the grid only earns the feed-in tariff, ranging from 5 c to 14 c per kWh, depending on your location and electricity plan. Solar electricity used on-site, rather than exported, saves you paying the grid tariff, typically around 20 c to 35 c per kWh.

Surprisingly, our modelling of the economics found that a 5 kW system now has a shorter or equivalent payback time to the 2 kW system. We studied the economics by simulating a large number of scenarios in half-hour intervals for a whole year using Sunulator, ATA’s free solar feasibility calculator.

Our primary economic measure is payback time, the number of years until bill savings recoup the installation cost—the fewer years the better. Payback times shorter than 10 years are generally considered attractive to solar customers, as the system is likely to pay for itself before any significant expenses, such as replacing the inverter. The panels should last at least 20 years, so cumulative bill savings are large, especially for a larger system.

To do the modelling, we assumed a feed-in tariff of 11.3 c/kWh in Victoria and in other states a doubling of feed-in tariffs from current levels, phased in over the next five years. We considered common grid tariffs in each capital city, for a variety of household consumption profiles, along with likely tariff increases (we used AEMO’s retail tariff forecasts, but since they were based on Hazelwood closing in 2020, which happened this year, we pulled them forward by three years; this allows for annual tariff rises between 1.5% for Queensland and 3.4% for Tasmania). Panels are assumed to be north-facing with a 20-degree tilt. Our analysis also includes panel degradation over time.

Read the full article in ReNew 140The full report on solar sizing, including references, is available at www.ata.org.au/news/bigger-solar-is-better-ata-report

 

Pomona

Battery storage gets competitive

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

It seems the convergence of environmental realities and the economics of renewables is finally escalating apace. While large-scale wind and solar farms have been the big focus of the last few years (and continue to be), large-scale battery storage has become ‘the next big thing’.

Globally and domestically, governments and corporations are rolling out big storage projects that will provide the missing link between renewable energy generation and grid stabilisation/meeting peak demand.

READ MORE »

In a few months, Germany will accept delivery of Europe’s biggest battery—a 48 MW/50 MWh lithium-ion unit—that will help provide grid stability in the Jardelund region near the border with Denmark, which currently relies on intermittent wind power. In the USA, its largest battery storage facility, the 20 MW/80 MWh Pomona Energy Storage Facility in Southern California, opened in January this year. India’s first (10 MW) grid-scale battery storage system was also launched in January, and Bloomberg New Energy Finance is slating that 800 MW of storage could be commissioned by 2020.

In Australia, in the wake of South Australia’s recent ‘crisis’ of energy supply, a key response from the SA Government has been to support the construction (by winning tender, before year’s end) of a 100 MW battery —Australia’s largest to date—with $150 m from a renewable technology fund. There have been 90 expressions of interest from 10 countries. [Update: this tender has now been awarded.]

One of the companies competing, Australia’s Lyon Group, has said that, regardless of the outcome of the tender process, it will build a $1 b battery and solar farm—believed to be the world’s biggest—by the end of this year, in SA’s Riverland region: 3.4 million solar panels and 1.1 million batteries will generate 330 MW of electricity and provide 100 MW/400 MWh of battery storage (depending on configuration). The project is fully financed, with grid connection already well progressed. The company’s 120 MW solar/100 MW/200 MWh battery Kingfisher project in SA’s Roxby Downs is also due to start construction in September 2017, to be running by June 2018. A third smaller storage project of 20MW/80MWh is also being developed on Cape York.

The Victorian Government recently announced a $20 m tender, as part of its $25 m Storage Initiative, which calls for proposals detailing the construction of large-scale storage facilities in the state’s west. Applications close mid-June and, from the process, the government aims to deploy up to two projects that will provide at least 100 MWh of battery storage by January 2018.

The ACT’s Next Generation Storage Program is committed to providing around 36 MW of distributed battery storage, through subsidised residential batteries, which plans to see 5000 homes signed up by 2020. And in the Northern Territory, results of a tender for 5 MW of battery storage (the nation’s largest, until the SA and Vic announcements, above) are about to be released.

Feature image: A peek into the Pomona Energy Storage Facility; at 20 MW/80 MWh, currently the largest in the USA. Image: Pomona Energy Storage, courtesy AltaGas Ltd

Hydrogen fuel cell powered train

Hydrogen as a fuel – is it viable?

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Is the hydrogen economy ever going to happen and are fuel cell vehicles really a viable alternative? Lance Turner cuts through the hype and takes a realistic look at using hydrogen for transport and energy storage.

ANYONE interested in renewable energy will have come across numerous articles on hydrogen fuel cells, and in particular, their use in cars and other transport as a potentially greener replacement for conventional internal combustion engine (ICE) drivetrains. However, to date there are very few fuel cell vehicles on the roads, apart from a few in demonstrator fleets, all subsidised by either the government or vehicle manufacturers.

READ MORE »

So why haven’t we seen the fuel cell revolution as promised? There are a number of reasons, but let’s first look at the basics of fuel cells.

 

What is a hydrogen fuel cell vehicle?

In its simplest form a hydrogen fuel cell consists of two electrodes (an anode and a cathode) separated by an electrolyte. Hydrogen gas is introduced at the anode and oxygen from the air at the cathode. The two combine to produce electricity, heat and water.

In a fuel cell vehicle, hydrogen is stored in high-pressure tanks and delivered to the fuel cell at a reduced pressure, while air is passed through the fuel cell stack (the common term for a number of fuel cells in a single unit) courtesy of an electrically driven compressor system. By varying the rate of gas flow through the stack, the electrical output of the fuel cell system can be controlled.

The electricity then normally passes through a DC to DC converter to produce a voltage suitable for the vehicle’s drive motor and battery bank (or ultracapacitor bank).

The resulting electricity powers one or more electric motors, which propel the car— exactly like a battery-based electric vehicle.

As mentioned, fuel cell vehicles include a battery or large ultracapacitor for temporary energy storage. This is required as a fuel cell takes a small amount of time to respond to gas flow rate changes. In a vehicle this would be an unacceptable delay—imagine putting your foot down only to have the car do very little for a couple of seconds. The battery and/or ultracapacitor store a relatively small amount of energy but they can deliver it immediately as a large amount of power. They also provide extra power when the total demand exceeds that available from the fuel cell stack (which usually has a lower maximum power output than the motors are rated for) such as when overtaking and hill climbing.

Indeed, the main difference between a purely battery electric vehicle (EV) and a fuel cell vehicle (FCV) is that the FCV has a combination of fuel cell system and small battery rather than a single large traction battery—in most other respects they are quite similar.

To store a usable amount of hydrogen in a small space, such as required for a vehicle drive system, you need to compress it enormously. How much does it have to be compressed? To gain acceptable ranges comparable to a typical petrol car or current long range EV (400 km or more), the level of compression is many hundreds of times atmospheric pressure.

Both Honda with their Clarity FCV and Hyundai with their ix35 vehicle use a maximum tank pressure of 700 Bar, or around 700 times normal atmospheric pressure, 70 megapascals, or over 10,000 psi in the old of pressure per square centimetre of tank surface area. terms. In more common terms, that’s 700 kg

Read the full article in ReNew 139.

the-project-created-4300-direct-indirect-and-induced-jobs-with-over-1000-workers-on-site-during-peak-construction-1000px

100% renewables – how feasible is it?

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

With ongoing discussion by government and media about the effect of renewables on the grid, the ATA’s Andrew Reddaway and Damien Moyse consider the feasibility of 100% renewables for Australia.

THE ATA (ReNew’s publisher) supports a transition from fossil fuels to renewable generation in Australia’s electricity grid.
As well as being important to meet our international commitments to fight climate change, this brings other benefits such as improved local health outcomes, greater energy security and more jobs.

READ MORE »

However, as this transition progresses we must ensure the grid remains reliable and avoid economic hardship. How can this be achieved as we approach 100% renewables? This article considers the challenges of relying on intermittent generation, ways to address those challenges and a plan for moving forward.

Read the full article in this month’s longform.

Read more articles in ReNew 138.

credits-onshore-wind-turbine-franseska-mortensen-and-samso-energy-academy

Island of energy: community-owned and renewable

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Denmark’s Samso Island went from complete reliance on imported oil and coal to 100% renewable electricity in just a decade. Jayitri Smiles and Nicky Ison explore the community and government partnerships that made it happen.

DURING the global oil crisis in 1973, Denmark began to think creatively about how to supply cheap energy to their population. As they built their first wind turbine, they were unknowingly establishing themselves as future world leaders in renewable energy.

READ MORE »

Today, Denmark aims to have renewable energy powering 100% of their country by 2050 and to eliminate coal usage by 2030. These targets build on a track record of success: since the 1990s Denmark has witnessed the quadrupling of renewable energy consumption.

The creation of the world’s first fully renewable energy powered island, Samso, is an exemplar of Denmark’s leadership. Not only has Samso become a carbon-negative region, but it has accomplished this world-first using community investment.

In 1997, Denmark’s Minister for Environment Svend Auken was inspired at the Kyoto climate talks. He returned home with a passion to harness the collective efforts of local Danish communities in a way that promoted self-sufficiency in renewable energy. Auken held a competition, which encouraged Danish islands to consider how their clean energy potential could be achieved with government funding and matching local investment.

The most compelling application came from Samso, a small island west of Copenhagen with a population of 4100. This island of 22 villages, at the time run purely on imported oil and coal, was suddenly thrust into the global spotlight and, through a combination of local tenacity, investment and government funding, transitioned to 100% renewable power in just a decade.

At the heart of this energy revolution sit Samso’s community-owned wind turbines. Onshore turbines with a generation capacity of 11 MW offset 100% of the island’s electricity consumption. Another 23 MW of generation capacity from ten offshore turbines offsets Samso’s transport emissions. Most (75%) of the houses on the island use straw-burning boilers via district heating systems to heat water and homes, and the remainder use heat pumps and solar hot water systems.

The extraordinary result is a carbon-negative island and community. The island now has a carbon footprint of negative 12 tonnes per person per year, a reduction of 140% since the 1990s (compare this to Australia’s footprint of 16.3 tonnes per person in 2013 and Denmark’s overall footprint of 6.8). Not only is the island energy self-sufficient, they now export renewable energy to other regions of Denmark, which provides US $8 million in annual revenue to local investors.

And Samso is not slowing down. Highly motivated, knowledgeable and passionate locals are aiming for the island to be completely fossil-fuel free by 2030. They plan to convert their ferry to biogas and, despite already offsetting their vehicle emissions via renewable energy generation, residents of Samso now own the highest number of electric cars per capita in Denmark.

 

Read about their transition in ReNew 138.

tau-pv-project-2016

Islands in the sun (and wind)

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

The idea of moving to renewable energy generation is proving attractive to many smaller communities, particularly island-based communities. Here are some of them.

Kangaroo Island: Currently powered by a 15 km undersea cable from mainland SA which is nearing the end of its design life, one option, moving the island to renewable energy generation, has been examined by UTS Institute For Sustainable Futures. The outcome of the study was that the cost of replacing the undersea cable would come in at $77 m whereas a local wind/solar/diesel hybrid system was estimated at around $87 m. However, once ongoing costs such as network charges are factored in, costs for the new cable option rise to $169 m, compared to $159 m for local supply. The system would likely include doubling the existing 8 MW diesel generation capacity, installing between four and eight wind turbines, adding five hectares of solar farm and around 800 solar rooftops. The end result would be 86% renewable and 14% diesel generation.
www.bit.ly/KangUTS100

READ MORE »

Isle of Eigg, Scotland: In 2008, the island’s electrification project was switched on, providing 24-hour power for the entire island. Previously, electricity had been provided by individual households using their own generators, resulting in excessive noise, pollution and high maintenance burdens on individuals. The project included laying of 11 km of cable and installation of three hydroelectric generators—100 kW at Laig on the west side of the island, with two smaller 5 to 6 kW hydros on the east side. Four small 6 kW wind turbines below An Sgurr and a 50 kW photovoltaic array round out the system. There are also backup generators for periods of low renewable input. To prevent overloading of the grid, each house has a maximum power draw of 5 kW, and 10 kW for businesses. When excess renewable energy is being generated, the electricity is used to heat community buildings.
www.islandsgoinggreen.org

Bruny Island, Tasmania: As looked at in ReNew 136, the CONSORT Bruny Island Battery Trial is an ARENA-funded project to install up to 40 battery systems on the island, with the view to stabilising the grid and reducing the use of diesel generation during the peak season. Households that participate in the trial will be provided with a large subsidy to install solar power and a smart battery storage system. They will also be able to sell their stored energy into the electricity market via Reposit Power. So far, the first round of participants have been selected. www.brunybatterytrial.org

Rottnest Island: The Rottnest Island Water and Renewable Energy Nexus project involves the construction of a 600 kW solar farm to complement the existing 600 kW wind turbine, which was installed in 2005 and already produces around 30% of the island’s electricity needs, saving more than 300,000 litres of diesel a year. The solar farm is expected to push the renewables portion to 45%, further reducing the need for diesel fuel. Funding for the project will be jointly provided by the Rottnest Island Authority ($2 m) and ARENA, which will provide $4 m. www.bit.ly/RottnestSust

King Island: The King Island Renewable Energy Integration Project (KIREIP) aims to increase the island’s renewable energy generation to around 65%, and up to 100% at times, while reducing the reliance on diesel fuel. By adding energy storage and energy flow control, the system allows greater contribution of power from renewable sources. Integration of smart grid technology provides the ability to control customer demand to match the available renewable energy supplies. The storage system, the largest electrochemical battery ever installed in Australia, is capable of producing 3 MW of power and storing 1.6 MWh of usable energy.
www.kingislandrenewableenergy.com.au

Island of Ta’u: The island of Ta’u in American Samoa lies around 6400 km off the west coast of the USA. Until recently it was entirely diesel-powered, with diesel being delivered by ship. Disruptions to deliveries had at times resulted in severe electricity restrictions—not great when you rely on electric pumps for basic water requirements. Ta’u now has a solar power and battery microgrid that can supply nearly 100% of the island’s electricity requirements from renewable energy. The new microgrid has all but eliminated power outages and greatly reduced the cost of providing electricity to Ta’u’s almost 600 residents. The system consists of a healthy 1.4 MW of solar generation capacity from SolarCity, which feeds into 6 MWh of grid-grade storage from Tesla (Tesla recently aquired SolarCity) consisting of 60 Tesla Powerpacks. The project was funded by the American Samoa Economic Development Authority, the US Environmental Protection Agency, and the US Department of Interior. It is expected to offset more than 400,000 litres of diesel per year.
blog.solarcity.com/island-in-the-sun

Read more in ReNew 138.

fronius-hybrid-diag

Just add batteries

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

There’s more to consider than just the brand or size when adding storage to a solar system. Damien Moyse and Nick Carrazzo highlight some of the issues to consider in a field with ever-evolving technology.

There are multiple ways that batteries can be added to an existing or new solar PV system. These different configurations will influence the system’s capabilities so it’s important to carefully consider the approach you take. This article covers the most common approaches currently available in Australia, but note that technology and options are developing rapidly so we will be updating this advice regularly.

READ MORE »

The majority of solar PV systems currently installed in Australia are unlikely to be ‘battery-ready’—an existing solar customer cannot simply purchase a lead-acid, lithium ion, flow or sodium battery and have it retrofitted to their existing system.

The solar panels can be retained, of course, but an additional or replacement inverter and charging components will likely be needed to charge and use the batteries.

One approach (DC coupling) involves replacing the existing grid-interactive inverter with a new hybrid inverter; such inverters can both control charging of the battery and conversion of electricity from DC to the AC required for household use. As a cheaper alternative, in a fairly recent development, the replacement of the grid-interactive inverter can be avoided through fitting a DC to DC converter between the solar array and the battery bank—thereby negating the need to replace the existing grid-interactive inverter.

A second approach (AC coupling) requires installation of a second battery-dedicated hybrid inverter (with integral charger controller), with the existing grid-interactive inverter retained.

As such, almost all the new battery products currently on the Australian market are either sold with a new inverter (some as part of an integrated ‘all-in-one’ storage unit and some with the inverter separate from the battery) or require an inverter to be purchased separately.

Thus, most existing solar customers will need to replace their existing grid-interactive solar inverter, add a second inverter or add a DC to DC converter to their system. Which approach is taken depends on whether the system uses AC or DC coupling and the capabilities required of the system. Coupling refers to where within the system the batteries are connected.

Read the full article in ReNew 137.

tassie-off-grid

Tassie off-grid home

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Given their distance from the nearest power pole, it made sense financially as well as philosophically for this Sydney couple to go off-grid in their new home in Tasmania. Peter Tuft describes how they went about it.

As we approached retirement my wife Robyn and I knew we did not want to spend the rest of our lives in Sydney. Sydney’s natural environment is glorious but it is also much too busy, too hot and humid in summer, and our house was too cold and hard to heat in winter. We had loved Tasmania since bushwalking there extensively in the 1970s and it has a lovely cool climate, so it was an obvious choice.

READ MORE »

We narrowed the selection to somewhere within one hour‘s drive of Hobart, then on a reconnaissance trip narrowed it further to the Channel region to the south. It has lush forests and scattered pasture with the sheltered d’Entrecasteaux Channel on one side and tall hills behind—just beautiful. And we were extraordinarily lucky to quickly find an 80 hectare lot which had all those elements plus extensive views over the Channel and Bruny Island to the Tasman Peninsula. It was a fraction of the cost of a Sydney suburban lot.

The decision to buy was in 2008 but building did not start until 2014 so we had plenty of time to think about what and how to build. We have always been interested in sustainability, and renewable energy in particular, even before they became so obviously necessary: my engineering undergraduate thesis in 1975 was on a solar heater and Robyn worked for many years on wastewater treatment and stream water quality. There was never any doubt that we would make maximum use of renewable energy and alternative waste disposal methods.

From the beginning we knew the house would be of passive solar thermal design. The house sits high on a hill (for the views!) and faces north-east. The main living room is entirely glass-fronted, about 11m long and up to 4m high with wide eaves. That allows huge solar input to the floor of polished concrete. A slight downside is that there is potential for it to be too warm in summer, but we’ve managed that with shade blinds and ventilation and so far it has not been a problem. All walls, floor and roof are well insulated, even the garage door, and all windows are double-glazed. Supplementary heating is via a wood heater set in a massive stone fireplace chosen partly for thermal mass and partly because it just looks awesome. Warm air from above the wood heater convects via ducts to the bathroom immediately behind the chimney, making it very cosy indeed.

Read the full article in ReNew 137.

powerwall

Australia’s first Powerwall home

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Nick Pfitzner and family are the proud owners of the first Tesla Powerwall home in Australia. Nick Pfiztner describes their configuration and the lessons they’ve learnt so far.

Our household had the privilege of the first Tesla Powerwall installation in Australia (maybe the world, they say). It has been a very interesting experience so far, and we’ve learnt a lot about what makes the house tick from an electricity point of view.  I’ve also had the opportunity to discuss the energy generation landscape with several organisations developing similar energy storage technologies.

READ MORE »

As a self-described Elon Musk fanboy, I became seriously interested in energy storage for our house after the Tesla Powerwall launch in 2015. I knew about other home storage systems, but mostly associated them with lead-acid systems and off-grid enthusiasts. We had previously got a quote for an off-grid AGM lead-acid system at one point, but we didn’t have the finance or space to make the BSB (big steel box) happen at that time.

However, by late last year with our finances more in order, we decided to take the plunge with the Powerwall. We chose Natural Solar as the installer. They had advertised themselves as the first certified installer of Powerwall in Australia and helped guide us through the options available.

We opted for 5 kW of Phono solar panels with a SolarEdge inverter and, of course, the Powerwall, for a total cost of $15,990 installed.

And add Reposit grid credits

Natural Solar also informed us about Reposit Power, a software package designed to maximise the benefits of home storage for the consumer. In a nutshell, Reposit is a software-based controller for the entire system. It learns the household usage patterns, gathers weather forecast data and interfaces with the inverter to make decisions about import or export of energy based on two important concepts:

Tariff arbitrage. This is the practice of switching to a time-of-use grid tariff and charging the battery at times advantageous to electricity pricing. This may occur when solar PV generation predictions for the next day are poor or where energy storage has been used up overnight. In either case, off-peak power can be imported for use the next morning.

GridCredits. This is an ARENA-supported project to investigate the use of intelligent storage and distribution of power via consumer-level battery systems, with the aim of reducing network infrastructure costs in future. Consumers are rewarded not through feed-in tariffs based on intermittent solar generation, but rather guaranteed power delivery from the battery. When the wholesale market for electricity is especially high, the electricity retailer discharges electricity from the battery into the grid, paying the consumer $1 per kWh.

These two factors could assist with the financial equation, so we figured it was worth the add-on cost of installing Reposit—an extra $800 at the time.

Read the full article in ReNew 137.

Fronius Primo 5.0 Single phase 5kw inverter_1

An inverter buyers guide

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Whether you live off-grid or have a grid-connected generation system, the right inverter can make all the difference. We check out what’s available, where to get them and which one is right for you.

Choosing an inverter may not be the first thing that comes to mind when you’re thinking about installing a solar or solar + battery system. But every one of the 1.5 million solar systems already installed in Australia includes an inverter and, in fact, it can be thought of as the ‘heart’ of the system—if it’s not working, your solar generation is wasted or, if you’re off-grid, you’ll be without power (or at least without mains-equivalent 240 volt power*).

READ MORE »

But what is an inverter and why is it so important? In a nutshell, an inverter takes electricity from a power source that produces DC electricity, such as solar panels or a battery bank, and converts it into mains-equivalent power (240 volt AC), ready to be used in your house.
It is important to have a good inverter. In off-grid systems, if your home relies solely on 240 volt power from a stand-alone inverter and the inverter fails, you will have no power, even though it is still being generated and stored. In grid-connected systems, an inverter failure means your solar panels are doing nothing until the inverter is repaired or replaced.

Which inverter for your needs?
The majority of currently installed grid-connected solar systems will be using a grid-interactive inverter. A grid-interactive inverter converts the energy from solar panels into mains power and feeds it into the house’s electrical wiring—no storage is involved. As indicated by the name grid-interactive, these inverters can export energy into the grid, and require a grid connection (or an equivalent 240 volt AC supply) to operate; they can’t operate in a stand-alone capacity.

When you bring energy storage into the equation it gets a little more complex, as the inverter needs to deal with both a generation source (like solar panels) and batteries; and possibly also the grid.

In off-grid systems, a stand-alone inverter can be used to convert the DC electricity from the battery bank into mains-equivalent power to run standard appliances. An inverter-charger is like a stand-alone inverter except that it has a mains voltage level input, which can be used to charge the batteries from the mains or a generator—it is not, however, grid-interactive, so can’t export energy to the grid.

The most complex inverter type is the hybrid inverter, which can feed energy into the grid from either the solar array or the battery bank. Many hybrid inverters can also power the house from the batteries during a power failure, in effect becoming a large UPS (uninterruptible power supply). They can also charge the batteries from the grid.

This makes many hybrid inverters true bi-directional devices, and many, if not most, can handle all of the energy flows in a home energy system. Some can even divert the excess solar energy to a particular load, such as a water heater, replacing the need for a separate device, known as a solar diverter (the SunMate is one example), for this purpose.

Let’s now look at the features of each type of inverter in a bit more detail.

Grid-interactive inverters
Grid-interactive inverters are connected to both the power source (usually a solar array but sometimes a wind or hydro turbine) and the mains power grid. Energy generated by the power source is converted to AC mains power of the correct voltage and frequency and this supplements the power drawn from the grid by the home’s appliances. At times there will be more energy generated than being used and the excess is fed into the mains grid. At these times you will accumulate export credits, although how much you get paid for those depends on your feed-in tariff.

Grid-interactive inverters vary enormously in size, from 10 kW or larger units for big domestic and small commercial systems, down to tiny 200 watt models. Some, known as microinverters, are even designed to be mounted on the back of a solar panel to make the panel itself a grid-interactive module. These are ideal for those who want to start small and increase their system over time, or for systems where the array may be partially shaded—in a solar system using microinverters, each panel is independent of the others and not affected if other panels are shaded.

Read the full article in ReNew 137

For the full tables from this guide in PDF format, click here

Renewable energy courses

Renewable energy courses guide

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

We’ve updated our renewable energy courses guide ready for enrolment time. You’ll find the table of courses—from TAFE certificates to postgraduate degrees—here. In the article, Anna Cumming has a look at what’s new in the industry.

IN the two years since we last published a review of the renewable energy courses available in Australia, things haven’t all been rosy for the renewable energy (RE) industry. Months of uncertainty at federal level over the national Renewable Energy Target, funding cuts to climate-related science, and the scaling back of feed-in tariffs for solar generation have all contributed to a reduction in the size of the industry.

READ MORE »

The latest available Clean Energy Council (CEC) figures put the number of people employed in the wider RE industry at 14,020 for the financial year 2014–15, down a big 27% from the peak of 19,120 in 2011–121. However, the CEC puts some of this contraction down to a consolidation of the small-scale solar industry to more stable and sustainable levels. It also notes that RET legislation was passed right at the end of the reporting period, and since then confidence has grown: “The mood across the industry is upbeat in 2016, and it is expected that job figures will begin to grow once project development begins in earnest again under the RET in the coming years.”

David Tolliday, Renewable Energy Training Coordinator at Holmesglen in Victoria, shares this feeling. “The initial RE boom [homeowners taking advantage of rebates and premium feed-in tariffs to install solar PV] has passed, and the solar install industry has settled to around 4200 accredited installers—a good sustainable number,” he says. “The big opportunities now are in bigger-scale stuff like commercial solar, and battery storage on grid-connected systems.”

So, how to get involved? For those wanting to get into the industry or upskill, there is a wide variety of training and courses to choose from, from undergraduate and postgraduate university courses in engineering or focused on broader energy strategy, to hands-on solar design and install certificates offered by TAFEs and private registered training organisations (RTOs), and even free online MOOCs (massive online open courses). See our previous RE courses guide in ReNew 129 for a comprehensive look at the types of courses available, prerequisites and typical training pathways; here, we look at what’s new since 2014.

Download the table of renewable energy courses here (130KB).

Read the full article in ReNew 137.

csr-bradford-solar

Finding value in sharing

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Can we find value for both customers and the network in sharing locally generated energy and thus accelerate a transition to 100% renewables? Bruce Thompson and Paul Murfitt discuss the potential in microgrids, virtual power plants and more.

The transformation of the electricity network is certainly now upon us. Years of environmental advocacy, rapid technology advances and shifts in consumer demand are driving an unprecedented shake up of our century-old supply network. With this change come opportunities (and some risks) to harness the value of renewable energy across the grid as we drive towards zero emissions.

READ MORE »

Traditionally, Australia’s electricity networks were largely built and controlled by state governments, and operated as central power supply systems managed with two policy imperatives in mind: security of supply and cost-effectiveness. The much-heralded disruption is turning this system upside down, bringing technical and financial challenges along with opportunities.

The big shift to date has been ‘behind the meter’, where there is a clear case for householders and businesses to invest in solar PV to avoid the cost of conventional energy supply. Yet establishing value ‘in front of the meter’—sharing your locally generated energy across the grid—has so far been fraught.

With the tapering off of feed-in-tariffs, owners of solar have been frustrated they don’t receive a fair price for their homegrown generation. On the other side of the fence, network operators have been aggrieved by the need to manage the technical impacts of solar PV and wind while their business model ‘death spirals’ from lower consumption.

Beyond the angst, new models such as microgrids and virtual power plants are starting to demonstrate that sharing solar PV generation and battery storage across the grid can leverage the opportunities and help manage the risks inherent in Australia’s changing electricity sector. For customers, potential benefits include access to wholesale pricing and retail tariffs. For networks, there can be lower costs from local control and load management, particularly if the models can reduce peak demand and avoid the need for network infrastructure augmentation.

Of course, the value of sharing locally generated energy across the grid is dependent on the time of day, the time of year and the location. The key challenge for ‘in front of the meter’ solutions is not only to understand the technology, but also to apply the fundamental principles of supply and demand to determine where the greatest value can be realised.

Bruce Thompson recently joined GreenSync as the Community Development Director following 12 years at Moreland Energy Foundation Ltd (MEFL) as major projects director. He is also the outgoing chair of the Coalition for Community Energy (C4CE). Paul Murfitt was recently appointed director of energy efficiency for the Victorian Government and is the outgoing CEO of MEFL.

Read the full article in ReNew 137.

mooroolbark

Neighbourly sharing: mini-grid in Mooroolbark, community battery in WA

Share : Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

Neighbours in the Melbourne suburb of Mooroolbark are set to share their energy generation via a mini-grid in an Australian-first trial run by AusNet Services. Eva Matthews finds out what’s involved.

IN AN Australian first, network provider AusNet Services is currently rolling out a solar + storage mini-grid trial in Mooroolbark, in Melbourne’s east.

READ MORE »

Of the 16 homes on the chosen street, 14 will each have between 3 and 4.5 kW of solar panels and a 10 kWh battery storage system installed, with a cloud-based monitoring and management platform to optimise power flows across the mini-grid and to provide demand management support to the network.

The two-year trial was announced in April and was made possible with funding from the Demand Management Innovation Allowance. Participants don’t pay for the equipment and, at the end of the trial, get to keep their panels and inverter (but the control system and battery storage go back to AusNet Services).

As at end August, all houses have solar panels, inverter and battery storage installed, enabling data gathering on energy generation and usage patterns. The control system should be in by end October, which is when testing can begin in earnest. Testing will include deciding when to charge and discharge the batteries, and at what rate, based on current and forecast customer usage and PV generation as well as the network requirements. A single objective (e.g. minimising the overall peak demand on the mini-grid) can be implemented in a number of ways, so they will be developing and testing different approaches. The stabilising device and switching equipment that enable the mini-grid to be islanded (isolated from the rest of the network) will be installed towards the end of this year.

The group of houses will operate as a mini-grid from a control and electrical point of view, but the metering and billing arrangements are unchanged. To enable financial offsetting of one participant’s generation against another’s usage would require different meters to be installed—with a parent meter for the mini-grid and sub-meters for each house—so instead they will be modelling the potential financial effects.

Two households were unable to participate in the trial; however, this will provide fortuitous real-world data for where there is less than 100% opt-in—testing how the mini-grid can serve the energy needs of these houses without having their energy contribution in the mix. AusNet Services’ Distributed Energy and Innovation Manager Justin Harding explains, “Those houses will simply appear as extra loads in the mini-grid. For example, if we are trying to reduce the net demand of the mini-grid to zero at the connection point to the main grid, all houses would need to export a small amount of energy to offset the non-participants’ load.”

Simone and Joel Beatty make up one of the households participating in the trial. When they purchased their home five years ago, Simone says they noticed that a lot of the new houses being built were having solar installed, and it was something they were interested in, but hadn’t been able to afford. So when AusNet Services came knocking on their door with news of the trial, Simone says they were “definitely excited.” As well as looking forward to seeing how it all works, and the impact on their electricity bills, Simone says they have also benefitted from the information provided by AusNet Services—how they can log in to a web portal to monitor their electricity usage and ways in which they can be more energy efficient. She says they have “definitely already altered some behaviours.” And not only has there been an educational side effect of having the technology installed, it has given the neighbourhood something in common to talk about and get excited about. Simone says “everyone seems very positive about it” and adds that friends and family are jealous!

This trial follows a three-year battery storage trial by AusNet Services that tested how residential batteries can reduce customer’s maximum demand for electricity and support the network. Justin Harding says that there will likely be an “evolution of trials” into the future. This Mooroolbark trial has a strong customer learning and technical focus; the next step could be a larger project with more of a commercial focus, looking at how best to structure finances and customer agreements.

Tech used in Mooroolbark mini-grid:

  • 3 kW of panels (JA Solar) per house, except where customers had existing PV systems
  • 10 kWh lithium ion battery storage (LG Chem) per house
  • 5 kW battery inverter (Selectronic
    SP Pro) per house
  • Peak Response Unit (GreenSync) per house—a communications device for optimising power flows, includes 3G modem that talks to the main control system and battery inverter
  • cloud-based control platform (GreenSync’s MicroEM)—runs forecasting/optimisation calculations to enable locally generated/stored energy to be shared between homes, based on the needs of individual houses and the needs of the mini-grid
  • a separate 3-phase inverter and Toshiba battery system from Power Technology to keep the mini-grid stable when in islanded mode
  • switching cabinet with circuit breaker and protection relay to transition the mini-grid to/from the main grid, supplied by EIV.

Aims/benefits of the trial:

  • test how mini-grids can support the network, e.g. to better manage peak demands, reduce risk of system overload, defer capital expenditure
  • optimise value of the assets both for customers and the network, e.g. getting full value from battery storage when customers are grouped and there is one overriding control system versus single households exporting/importing energy to/from the grid
  • better understand household generation and usage patterns to help determine payment structures and tariffs, and test how energy self-sufficient a community can be
  • test potential for an uninterruptible power supply, i.e. where homes can be islanded, either individually or as a microgrid, and stored energy used if the grid goes down
  • investigate the performance of new methods to identify and mitigate electrical faults in a 100% inverter-based supply environment.

Best of both? Community battery trial in WA

A CUTTING-EDGE residential battery trial underway in the new Perth suburb of Alkimos allows residents to generate solar electricity and benefit from access to a ‘virtual storage’ battery system.

Led by local energy provider Synergy, in collaboration with Lendlease and LandCorp, the project involves a utility-scale grid-connected 0.5 MVA/1.1 MWh battery energy storage system located on-site in two shipping containers.

It has a number of aims: to reduce energy bills for participating households and improve network efficiencies by ultimately reducing connection costs. However, the most interesting and important aspect of the trial is Synergy’s ‘time of use’ billing product called the Peak Demand Saver plan.

The plan works by offering a three-part tariff for network energy, with different energy charges for peak daily (4 pm to 8 pm), off-peak day (midnight to 4 pm) and off-peak evening (8 pm to midnight). The time-of-use energy tariffs are designed to encourage households to minimise consumption and maximise returns on their solar PV investment—but without the need to invest in their own battery storage.

This new-style product means Alkimos residents pay a fee each month to have access to the community-scale battery storage. Those who store solar credits during the day draw on them first during the peak daily period, and then for the evening off-peak without incurring any additional costs, in much the same way they would their own battery.  During the day households use their own solar energy.

“It’s everybody’s battery to use. Customers pay $11 per month to use it, and then we calculate their usage over a 60-day billing period,” said Synergy.

“Anything they put into the batteries is theirs to draw on at peak times at no additional charge. And whatever they have left in the battery after the 60-day billing cycle is purchased from them at a 7 cents per kWh [feed-in tariff] rate. Because it is ‘virtual’ storage you can pretend it is your own battery, it’s just your neighbours are pretending it’s their battery too.”

So far, 65 residents have opted to participate in the trial since it began in April 2016 with the aim that 100 households will take part over the four-year trial period. Before residents join the trial, Synergy analyses their historical consumption to ensure the tariff suits their usage patterns.

“However, we’ve already had customers who want to participate even though they are not necessarily going to be better off, because they want to be part of the first shared battery trial in Australia,” said Synergy.

The trial will cost around $6.7 million and is backed with a $3.3 million Australian Renewable Energy Agency grant, and when launching the trial ARENA CEO Ivor Frischknecht said community-scale battery storage held great promise. “A new [housing] development like this might actually need less of a connection, or a smaller connection [to the electricity network]. That means lower costs for those people that are buying new lots and less investment into poles, wires and transformers,” he said.

For more info: www.synergy.net.au/Global/Alkimos-Peak-Demand-Saver-plan

Read more on microgrids in ReNew 137.