I have solar panels on the roof of my house that heat the hot water so we don't need to use Gas. The 6 months of the summer my gas bill was £6.52.... due to nominal use on the cooker. So basically for 6 months of the year the solar panels provide the hot water rather than using the gas heater. As 60% of the gas bill is from heating water, rather than central heating the home, we save massive amounts of cash. Over £1000 per year........ Solar I am all for!