It draws on weather forecasts to predict how much power solar panels will generate in the coming days and learns a household's consumption patterns so it can predict how much energy will be used each day and when.
Reposit is constantly calculating the best result for the householder, depending on the weather, likely demand on the energy market and the spot price of electricity - that is, how much power is selling for minute-by-minute on the wholesale electricity market.
For instance, on a sunny Tuesday a householder's solar panels would probably be producing a lot of energy and the spot price of power would be high because offices and factories are consuming more electricity to keep their staff cool. It might be a profitable time to sell power produced by the household solar panels on the wholesale market.
Alternatively, perhaps the weather forecast for the next few days is overcast, with little potential to generate much rooftop solar power. Reposit Power might wait until 3am, say, when cities are asleep and power usage and prices drop sharply, and buy cheap power from the spot market. This cheap electricity can top up the household battery with power that can be used when the price of electricity rises again.
This is great news for the consumer, who gets cheaper power.
But it's also good news for the environment. The system allows householders to either store or sell their excess solar power rather than let it go to waste and buy power from coal-fired generators later. Likewise, they can make use of the excess power that generators produce at times of low demand.
All up it means that cumulatively, we are using power more efficiently and hence will have to draw less on greenhouse gas emitting power sources such as coal.
Both solar generation and battery storage technology are marching ahead in leaps and bounds. As they continue to improve, we will be able to draw less and less on non-renewable sources of energy.
This is obviously important everywhere, but particularly so in Australia.
Political will to do anything about global warming has stalled. As with so many other potential reforms, including addressing our growing budget deficit and fixing our tax system, any debate about energy usage quickly descends into a scare campaign.
Someone need only mention that power prices might rise as a result of introducing a carbon tax or emissions trading scheme and politicians run a thousand miles from the idea, putting any genuine attempt to work on a solution into the too-hard basket.
In Australia, renewable energy has suffered a recent reversal of fortunes. This is largely the result of blackouts in South Australia, which leads the nation in renewable energy generation with about two-fifths of its power produced by wind and solar.
That is a laudable effort but at times - particularly on very hot days when everyone turns on their air conditioning - there isn't enough power to meet demand. This has led to blackouts in Adelaide several times in recent years and caused a great deal of scepticism about the effectiveness of green power.
The problem was caused because the high voltage cables linking South Australia with power from other states aren't large enough to handle spiking demand, meaning the state simply didn't have enough power.
Elon Musk, founder of US battery maker Tesla, has offered to save the state from blackouts by installing enough battery storage within 100 days (if he can't make this deadline he'll install it for free). The South Australian government is said to be examining the proposal.
The offer grabbed global headlines for Musk and whether it comes to fruition is yet to be seen. But it's another example of how the private sector and markets are stepping in where governments have failed.
While politicians argue and posture over the best response, science and the free market are making headway with global warming.
