Putting in a solar hot water system starts with analysis of your hot water needs. How much do you use, and what do you currently pay for it? Likely, you will never be able to replace your entire hot water supply with solar hot water, but anything you do now will help your bills in the future.
Beyond the solar collector – which will be between 4 and 12 feet long – you’ll need the following parts to complete a solar heating installation:
• Storage Tanks – For active systems using evacuated tubes, storage tanks will hold the potable water away from the roof. This allows you to heat the water in a separate location more safely in cold temperatures.
• Water Heater – If you choose to remain connected to the grid, with the option for outside energy to heat your water, this is important. Most people remain connected to be sure they never run out of hot water. If the solar tank drains when you have company or it gets too cold outside, this will be welcome.
• Heat Exchanger – If you are using coolant in your solar collectors, you’ll need pipes or coils to transfer the heat from the coolant to your water, usually inside your storage tanks.
• Water Pumps – In an active system, you’ll need water pumps to move water to and from your solar collectors. Passive systems don’t use water pumps.
• Valves and Controls – These are used in active systems as well. Controls will determine where water is pumped and when to turn on your hot water tank. You can also install an isolation valve to cut off your solar system if something goes wrong along with a tempering valve. If you’re using direct hot water from your solar collector, a tempering valve will make sure it doesn’t get too hot when you’re in the shower or washing dishes.
Hot Water or Heating
Of the two, hot water is considered the simplest to install because it uses less energy than heating and because it only requires two connections to existing plumbing. However, for many homes – especially new ones – it is viable to use a solar heating system for both hot water and heating. In the case of heating, you’ll need to install pipes and radiators throughout the house to transfer the heat to your rooms, which will require professional assistance.
Photovoltaic Solar Power
The second type of solar power – the one you’ve likely heard more about – is photovoltaic. Without getting too technical, photovoltaic solar power is the process of converting solar energy directly into electricity using a solar panel. These panels are made with highly conductive materials like silicon, which can break apart the energy from the sun’s rays into electrons and then direct them into an electric current. That current is transmitted through wiring in your home, converted into usable electricity, and funneled to your outlets and lighting fixtures.
It’s not quite as simple as all that, but nor is it much more complicated. Solar power’s biggest drawback isn’t complexity, but cost.
Because solar panels are notoriously inefficient (the best panels convert between 10– 15% of the solar energy that hits them), and because they take up so much space, a system that will fully power your home would be large and rather expensive.