The Virtual Power StationPosted: Friday, 18th November, 2011
Having electricity available at the flick of a switch is almost taken for granted nowadays in our homes and workplaces. But there’s a lot that has to go on behind the scenes for this to happen. In Australia, one mechanism that helps this take place is the fact that the electricity market pays a higher price for electricity that is dispatchable – that is, that can be reliably available when needed. As a matter of fact, in times of peak demand an electricity generator can be paid up to $12,500 per megawatt-hour – that’s well over 100 times the average price!
Good solar conditions, however, aren’t always guaranteed to be there when we need energy most. The image at the top of the page shows sunshine levels during the day on Saturday, when we had intermittent cloud in the morning followed by a nice sunny afternoon. If you have solar PV panels on your roof, on Saturday morning you wouldn’t have been able to guarantee a certain electricity output to the grid.
But imagine if you could guarantee to provide a certain amount of power at a certain time. Now imagine that it’s not only you but a network of others, all with solar panels as well, who can do the same. All of a sudden you’ve got a significant amount of capacity that you can dispatch when needed. This kind of sounds like a power station, right? Well that idea describes the ‘virtual’ power station: by working together to build significant capacity (and having the ability to control it) the whole becomes more valuable than the sum of its parts.
If this aggregate electricity generation can then be sold for more than what each participant would otherwise receive, each individual system owner has the potential to make more money. This in turn makes solar payback periods shorter and the technology financially attractive – as well as helping make our electricity supply more reliable.
Finding ways to improve situations like this is why CSIRO is running a project called the Virtual Power Station, or VPS. It’s a technology that can intelligently link together a whole lot of separate renewable energy generators, like solar panels or wind turbines, so that they appear to the grid like a single, predictable power station. If some energy storage systems are part of the network as well, the electricity can be dispatched at the times when the demand – and therefore the price – is highest.
This is more than a just concept. CSIRO and Lake Macquarie City Council are trialling a VPS system that connects 20 household and council solar PV systems and two battery storage facilities with CSIRO Energy Centre in Newcastle. The project team has obtained a wealth of information and even quickly diagnosed a faulty inverter (saving the homeowner from potentially what could have been a lot of lost generation and revenue!). I’ll be posting more about that trial shortly.
You can read more about the Virtual Power Station on the CSIRO website. There’s a great summary of what it’s all about here, and you can listen to scientist Dr John Ward discuss the project in this podcast. And if you’re in Newcastle, you can hear CSIRO research scientist Dr Adam Berry speak about the Lake Macquarie VPS trial in person on 22 November. Click here for details.