Solar Photovoltaic (PV) is a technology that works well to provide solar electricity suitable for running most of your electrical needs such as air conditioning, lighting, refrigeration, water pumping, etc. However, when it comes to thermal or heating needs, solar PV is not well suited.
Solar PV can provide thermal energy, but it will require many solar panels than usual making it expensive.
For cost-effectiveness purposes, solar electricity (PV) is a great supplemental source of electricity and when connected to the grid, it can help to reduce your energy costs for on-grid PV systems.
For off-grid PV systems, hybrid solar PV systems such as solar PV /solar thermal with geothermal heat pumps, or with wind power systems or with solar power generators can offer solutions to meet all your energy solutions.
Solar PV on its own can be an expensive energy option because you still need batteries to store excess power needed at night when there is no sunshine.
However, grid-connected PV systems can eliminate the battery cost. As such, during the day when your solar panels are generating power, it can be fed into the grid causing your meter to run backward helping to reduce your overall energy bill.
At night, this power can be drawn from the grid to power your household. At the end of the month, you can receive credit helping to reduce your energy bill.
Technological options to supplement your solar PV for thermal or heating needs.
During the day solar electricity can be used to run your air conditioning (in summer), refrigeration, lighting or water pumping for your pond, swimming pool, etc.
In winter, you might need to supplement your solar PV for heating or thermal needs. Thermal needs come in various forms, energy for cooking, energy for bath or energy for space heating, etc.
As such, the following energy options could be explored based on their cost, efficiency, and application:
- Net metering: Grid-connected solar PV is a great solution to supplement your solar PV for the thermal energy needs that your system may not be able to meet. This is one option that is cost-effective and widely applied in many homes in the USA.
- Geothermal Heat Pump for your home space heating or cooling: This is a renewable energy technology that has started to be applied for home space heating or cooling. It can be used to heat your home in winter and cool it during summer based on the fact that depending on latitude, ground temperatures range from 45°F (7°C) to 75°F (21°C). As such, the geothermal heat pump takes advantage of this by exchanging heat with the earth through a ground heat exchanger since this ground temperature is warmer than the air above it during the winter and cooler than the air in the summer. However, this technology is still being developed and the cost might be prohibitive for some people, but with tax credits and other financial incentives from the government, it might work based on your budget and energy requirements.
- All solar PV and solar thermal (heating): Rural areas that may be very far away from the utility grid might want to consider going all solar and using battery systems for storage to store excess energy produced during the day and using it at night. You might want to consider other renewable options such as geothermal energy or wind to supplement solar. All these options will depend on what technology is applicable in your situation and whether it is cost-effective or affordable. Solar thermal (heating) in homes is mostly used to heat water used for showering, laundry, and other household use.
All of the above options may or may not be feasible for your specific case and today with the advancement of software technology, you can use simple online tools like a solar panel cost calculator from the EnergySage to estimate for example, how many solar panels you need to power home and using their platform you can be guided when it comes to other energy options suitable for your specific case.