Why Solar Hot Water?

Why Solar Hot Water?

Alison and I decided to spend on renewable energy for our new home. After evaluating the choices, an evacuated-tube solar hot water heating system rose to the top of the list. We went with a local company, Simple Solar, to handle the installation.

Mature, Efficient Technology

Unlike solar photovoltaic panels which generate electricity at about 20% efficiency, evacuated-tube solar collectors operate at 80% efficiency or better. Basically, heating water efficiently with the sun is a solved problem with little room for improvements. On the other hand, generating electricity with solar panels clearly has lots of room for improvement. So we'll be holding off on solar photovoltatic panels for 5 years, hoping for a breakthrough in price and efficiency.

Best Payback Period

Renewable energy alternatives are often compared to fossil fuel energy solely on cost to buy and cost to run. In Alberta, that is a very challenging comparison given the currently low cost of natural gas. On such a pure payback comparison using today's fossil fuel prices, renewable energy sources such as solar thermal have payback periods extending over decades.

Factoring in the $10K Alberta government grant for a 86+ Energuide house, makes the payback quite reasonable. Then assume some reasonable price increases in natural gas over the coming years and solar thermal panels make a lot of financial sense.

Carbon Footprint

Since Simple Solar's panels include a small photo-voltaic panel to generate electrical power for the pump, the solar collector is completely carbon-emission free. We'll still be drawing a bit of natural gas for final "top-up" heating, but overall our domestic hot water heating needs will use a small fraction the natural gas of a regular house.