Ever get the idea that the decision to quit the grid – or not to connect – was reserved for low energy users, austere consumers or those with no possibility of connection?
Think again. Owners of ever large mansions with extraordinarily high levels of daily consumption are also deciding to cut the link to the grid – some times at phenomenal cost approaching half a million dollars.
Take this property picture above – showing the main house and nearby buildings, and a plan of its rooftop solar (not the actual installation, you can see that below).
The property – in the Yarra Valley just an hour’s drive from Melbourne – belongs to a businessman who had enough of near weekly outages from faults in the local network, and from the soaring cost of electricity.
The property’s average daily consumption was nearly 200kWh – or around $70 a day, which makes for an eyewatering amount over the year.
After consulting the likes of energy expert Glen Morris, of SolarQuip, and instaler Jerry Robinson, from The Green House Effect, that daily consumption has been clipped to around 100kW, and the property is now looking after its own energy needs.
It has installed 46kW of rooftop solar, filling every available space on sheds and car ports, and installed 300kWh of lead acid battery storage. Perhaps heroically, given the onset of Victoria’s winter, the owners has decided not to go with a back-up generator.
“We told him he should, but he said he would tough it out,” Morris says. “We’ll see what happens over winter. Now he knows he has finite reserve, so his consumption is falling further.”
Morris made a presentation of the installation at the recent Smart Energy Conference, in a discussion of correct sizing for batteries – both on and off grid.
The green line above shows energy generated by the solar system, the red line the amount consumed, and the shaded red section represents the accumulated total of consumption each day. Yellow is the state of charge of the battery.
Robinson says the owner has been thinking about the exit from the grid for around years. The owner uses a lot of electricity for the pool, heating etc.
But he plans to also get an electric vehicle – which will effectively be solar powered because for nine months of the year there will be more than enough excess power from the solar panels at its current capacity.
“Why wouldn’t you, he’s going to generate a ridiculous amount of power – on average 160kWh a day over the year. There will be a lot left over to go in the car.” Except for those last three months.
Robinson says big consumers are looking increasingly at off-grid options, or at least trying to match aggregate demand with their own production.
A few years ago he did an installation in Eaglemont, another house with 100kWh average daily consumption, to help power the wine room, the heated floors, the pool etc.
“They spent $100,000 on a three phase lithium battery with 18kW solar panels – that’s all we could fit on her roof. That’s what I call greening power because they could.
“Whatever you want you can have it now.”
Giles Parkinson is founder and editor of One Step Off The Grid, and also edits and founded Renew Economy and The Driven. He has been a journalist for 35 years and is a former business and deputy editor of the Australian Financial Review.
