What’s the difference between solar thermal and solar photovoltaics? Which is the best system for my pool or my house?
Solar Thermal produces heat, Solar PV electricity. The solution depends on the circumstances. There are two types of solar energy receivers: solar photovoltaic (solar PV or PV for short) and solar thermal. Solar PV produces electrical energy the other, heat. Thermal collects infrared light, and solar PV collects photonic light. Firstly let's focus on solar PV because that's presently a good application for your home as you undoubtedly consume a fair amount of power in the summer months due to pool filtration and heat pump pool heating.
Having said that solar thermal is great for solar heating the pool and a close roof to the pool plant room could be used to take solar thermal (and could take solar PV). In that case, the solar thermal would reduce the amount of time the heat pump runs. Solar PV will offset the amount of energy drawn in from the grid and reduce costs that way. Any time you produce more electrical energy than you need, it gets exported from your home via an export meter at your main consumer unit, and you get paid for it.
Whilst solar thermal is a great idea and in the longer term complements solar PV, it is undoubtedly trickier to install and maintain, so often heat pumps combined with PV win the day. At the Renew Guernsey home-base we have PV, thermal and a heat pump and we have many customers that do - it's the ultimate solution, but not practical for everyone. Solar photovoltaic panels whilst fairly expensive upfront are also relatively easy to install with minimal or no real maintenance - just an annual check is normally required, or the panels cleaned regularly depending on where you live. The cost has also come down a huge amount over the years, so they are extremely cost-effective to install and very economical regarding running costs – especially tied in with a pool.