An off-grid office for half the price? An Adelaide company says it has the technology
Cameron Jewell | 29 August 2017
A 3000-square-metre office building in Adelaide has gone through winter disconnected from the grid, thanks to a renewable energy system comprising concentrated solar thermal, solar PV, and both thermal and battery storage. And the company behind the project says it can construct similar prefabricated off-grid buildings for half the cost of a typical Green Star-rated office.
Federal energy minister Josh Frydenberg was on Monday at the $8 million, four-storey Fluid Solar House in Elizabeth Vale, 27 kilometres north of Adelaide CBD, to symbolically “cut the cord” at an “off-grid party” for the project, though perhaps also to score some political points by linking the project to South Australia’s recent grid reliability woes, which make off-grid an especially attractive proposition.
The commercial office building is a demonstration of company Fluid Solar’s renewable energy technologies that together allow a building to operate without drawing on the grid for support.
The key is a hybrid thermal and electrical energy system backed up by both thermal and electrical storage.
Fluid Solar House uses a 150-kilowatt concentrating solar thermal tube system to capture and store heat energy beneath its car park, which is then used to power the building’s HVAC and hot water systems, and provides energy for 60-70 per cent of the building’s needs. A 98kW solar system provides the energy required for other functions, such as lighting, lifts and appliance needs.
All up there is also about two megawatt-hours of energy storage; 90 per cent of this is thermal and the remaining 10 per cent conventional battery storage.
The building has been running without drawing grid energy since April, already saving about $28,000 in energy costs.
Managing director Roger Davies told The Fifth Estate he had installed a gas-fired generator as back-up in case his calculations went astray but “never turned it on”.
To the dismay of energy retailers, the building got through the winter without needing any grid support, and Davies is confident it’ll get through the summer too.
He believes that many new build projects have the potential to be made either as off-grid or “thin grid” (having the capacity to draw from the grid for a maximum of a few hundred hours a year).
There’s even potential for the thermal system to be retrofitted on building roofs as a pre-cooling or pre-heating strategy to cut current HVAC costs by 10-15 per cent, with it particularly suiting low-rise retail and shopping centre applications.
Prefabrication key to cutting costs
The building is also a demonstration of the company’s prefabricated construction offerings, which it says can cut building costs significantly.
Fluid Solar believes it can construct a medium-rise office building with no grid energy draw at half the cost of a typical Green Star-rated building, and also cheaper than a standard office.
For a medium-rise commercial office, it says it can construct at about $2500 a sq m, which it compares to about $5000 a sq m in “typical construction costs” for a Green Star building with annual energy consumption of 26kWh a sq m, and $3000 a sq m for a standard office building with 140kWh a sq m annual energy consumption.
The construction technique also offers unprecedented flexibility in how internal tenant spaces can be arranged.
“Over the lifetime it will be substantially cheaper to rejuvenate or renovate.
“It’s cost effective from a CAPEX point of view and very flexible.”
Apartments the next frontier
The company is also operating in the detached housing and apartment markets, with prefabricated designs that can be fitted with its renewable energy solution. A tiny house demonstration project is located on-site at Fluid Solar House.
The system uses steel-framed, Colorbond-covered panels filled with insulating foam, with electrical wiring, cabling and plumbing embedded in service conduits pre-designed into the panels.
Residential projects can be constructed from about $500 a square metre, with the renewable technology cutting operational energy costs significantly.
“With the cost of building houses largely driven by labour costs, our building system uses pre-designed modular components, transported in flat packs and assembled with metal fittings that plug together. Our system can assemble a four-bedroom home on a prepared site in less than four weeks,” Davies says.
“As well as an enormous speed advantage, we deliver the benefits of low on-going energy costs. Traditional homes consume from $1300 to $4000 each year in energy costs whereas a Fluid Solar home can reduce that figure by 90 per cent – or go off-grid altogether.”
Higher density developments are on the cards too. Davies already has approval for a two-storey, 20-apartment residential apartment complex at Munno Para, another northern Adelaide suburb.
Davies told The Fifth Estate he was working with financiers to investigate different models that would allow low-income households to rent homes at a low cost.
This could include a model similar to build-to-rent where a home and energy package could be offered for about $200 a week for a two-bedder.
“My intention is to make it affordable for people to live comfortably – not to be desperately hot in summer or in a freezing box in winter.”
He says he knows from personal experience that rental properties are typically poorly insulated and there are many people renting in Adelaide that can not afford to properly heat or cool their homes.
“The real challenge is to provide good quality housing at a price that people can afford.”
Forging a new future for Adelaide
There’s also potential for Fluid Solar’s technology to help shore up a manufacturing future for Adelaide.
The office is located just a kilometre from the closing General Motors Holden car plant, though Davies has a plan to become “bigger than Holden”, and indeed the prefabricated building system components, manufactured at a factory in Edinburgh, north of Adelaide, could potentially provide a place for Holden’s retrenched workers, as some similar skill set applies to off-site modular housing manufacture as it does to car part manufacture.
Davies says he visited the Holden job fair a couple of weeks ago and there were 80 interested Holden workers that may be able to move to his company, which was gearing up to start producing both its solar thermal technology and prefabricated panels.
A co-working space for Adelaide innovation
Fluid Solar House will be company headquarters, but Davies is also extending a hand to “like-minded” local entrepreneurs and start-ups to join a co-working space housed onsite.
Called the “Innovation Grid”, the space is designed to be “a hub for innovative technology and progressive collaboration, dedicated to supporting renewable energy and smart technology startups and SMEs to break through barriers”.
Rent starts from $25 a day for a seat at a hot desk, up to $850 a month (+GST) for a large office space suitable for three or more people. Features include meeting rooms, event spaces, informal breakout spaces, fast wifi, printing facilities, kitchen, parking and reception services. And no utility bills.
There is also a mentorship program designed to help start-ups move from idea generation to product distribution.
“The aim is to assist startups and entrepreneurs improve the efficiency, effectiveness, awareness of and availability of renewable energy around the globe and we believe that an entrepreneurial mindset along with innovative expertise is the way to do it.”
Interested Adelaide-based organisations can visit Fluid Solar to find out more.