Heating systems are essential for homes and apartments during the winter and their operating costs can be high in the colder months. However, there are many ways to use solar energy in space heater and domestic hot water applications, reducing your heating expenses.
- Unless you live in a remote location, electrical engineers will typically recommend a grid-connected solar power system.
- This improves reliability and your appliances can rely on the grid when the solar panels are not productive.
The effectiveness of solar heating will depend on the equipment used and its configuration. For example, an ENERGY STAR heat pump offers electricity savings of over 60% compared to a resistance heater. While a resistance heater can only provide one kWh of heat for every kWh of electricity, a heat pump can produce 2-4 kWh of heat per kWh of electricity.
Save on heating costs during the winter months with solar energy.
Even if your heating system uses fuels like natural gas, propane or oil, it will have electrical components like air handlers or hydronic pumps. Solar panels cannot reduce the direct cost of heating in these cases, but they can provide power for the electrical components of the heating system.
Combining Solar Panels with Electric Heating Systems
Ideally, solar panels should be combined with a high-efficiency heat pump as it maximizes the heating achieved per kilowatt-hour. A resistance heater converts electricity to heat less efficiently, which means two things:
- You will need more solar panels to offset your heating costs.
- You should rely more on local utilities since solar energy is used less efficiently.
Suppose you live in a city where the residential electricity rate is 16 cents/kWh. If you consume 1,000 kWh with an electric resistance heater, you will be charged $160 and receive 1,000 kWh of heat. However, a heat pump will produce more than 2,500 kWh of heat for the same cost and consumption. This same heating output would have cost $400 with a resistance heater.
The same goes for solar panels: 1,000 kWh output saves you just $160 if you use an electric resistance heater, but your savings increase to $400 when you combine solar panels with an efficient heat pump.
Using Solar Collectors for Hot Water
Another option is to use sunlight directly to heat water with a solar collector , and this system can be combined with solar panels. However, there are important differences between them:
- The electricity produced by solar panels can be used in any household appliance, not just heat pumps or resistance heaters.
- A solar collector only produces hot water. It can be used directly or can be circulated through space heating pipes.
In properties with sufficient space, it is feasible to use both solar panels and hot water collectors. However, when space is limited, solar panels are generally a better investment: their electricity can be used by any device and they can also cover air conditioning costs during the summer.
Heat pumps are also available for hot water systems and offer many advantages over resistance-based water heaters. If surplus electricity from solar panels is used to power a heat pump and store hot water, you can use it at night when the panels are no longer productive.
Using space heating systems during a blackout
Large swaths of the US were affected by blackouts during the February 2021 winter storm, leaving millions of people without heat. Using solar panels directly to operate a heating system during a blackout is impractical for several reasons:
- They do not produce electricity at night, precisely when the lowest temperatures arrive.
- Consider that winter storms bring cloudy weather, which reduces the productivity of solar panels even during the day.
A solar-powered heating system can be improved with energy storage , making it useful even during a blackout. A well-insulated tank can store hot water, while a home battery system can provide electricity for space heating, ideally with a heat pump. When the solar panels are productive, their output can be used to replenish either of the two storage devices.
Another advantage of this configuration is that it is not limited to solar panels, and can use other sources of electricity. For example, if your electricity tariff has variable prices throughout the day, you can charge your batteries and store hot water after midnight, when the lowest tariffs are charged. While this may not be possible during a blackout, a smart home system can be programmed in advance to always maintain sufficient battery charge and hot water. Solar panels are used during the day and cheap electricity is used after midnight.
Conclusion
Solar panels and efficient heating systems can achieve synergy by reducing energy costs during winter. Even if you have a combustion heater, solar energy can be used by the electrical components of the heating system. If the installation is combined with a home battery and an insulated tank, you can store electricity and hot water for blackouts. This feature is very useful if a winter storm causes extended blackouts in your area.
2021 and 2022 offer an excellent opportunity to install solar panels in the US, as Congress extended the 26% federal tax credit for two years in December 2020. This means you will receive a tax deduction of $260 for each $1,000 invested in solar energy.
