- Energy Saving
- Heat Pumps
- Electricity Generation
Energy efficiency is not just low-hanging fruit; it is fruit on the ground.Stephen Chu, US Secretary of Energy
Is solar thermal catching up with solar PV?
Solar thermal has been in the news lately, following the Solar Trade Association’s claim that the cost of solar hot water systems could fall by almost 30 per cent, if the market expands to catch up with solar PV.
I’ve always been a fan of solar water heating. It's ridiculously simple in concept and, despite the view that the weather is too cold in the UK for it to work effectively, the truth is that low-loss, high efficiency systems such as these can work comfortably in apparently quite chilly climates.
However, it's worth getting the potential of solar thermal heating systems into perspective...
The obvious application for a solar thermal system would surely be to heat space. However, don't be fooled — solar thermal simply doesn’t fit that purpose. The output temperature of a solar thermal system just isn't high enough, and it will give out the least heat when it's most wanted.
Where solar thermal really comes into its own is water heating. Complete heating, or pre-heating, of domestic hot water with a solar thermal system is a simple process. And because hot water is needed all year round (unlike space heating) it makes the best use of seasonal radiation. In addition, of course, heated water can be stored — so that midday sun can be captured for hot water applications later on.
So the news that the cost of solar water systems could be coming down is great news, and I hope we see more of them in the next few years.