Solar panels, without batteries, don’t work at peak efficiency. They are least efficient when households consume the least amount of energy. Energy generation is at its peak, but homes are mostly empty. During work and school hours, much of the produced energy is sent back to the grid. Solar panel batteries make it possible to store produced energy and consume it later when the sun goes down. Deciding if the investment is worth it depends on energy consumption patterns, and not on the presence of solar panels.
Impact of Adding a Battery
Solar panels, without a battery, provide energy to the grid as the energy is produced. With a battery, energy generation is now stored and energy can be consumed once solar panels stop producing energy, like during the night. Batteries shift the consumption of energy from the solar panels to a later time.
Who It Benefits
Batteries now have an important role and justify their costs if energy consumption is done during the evening hours, and if cooking, appliance use, and electric vehicle charging occur during these hours. If energy consumption is done during the hours of daylight, the role and justification of the battery significantly diminishes.
Also consider:
- Roof with and without obstructions and sun exposure factors into production. The battery will charge only with what the panels produce.
- Out of the house during the day and only home in the evening? That’s when batteries are most effective.
- Are power cuts common in your area? Some battery systems power select circuits during an outage.
The trade-offs
Batteries, in addition to the expense of the panels, take up space and add a line to the system that will require future replacement, similar to an inverter. Not every solar household needs one. A small roof with a small system or a household that is mostly out during the day means an even smaller benefit.
So is it worth it?
It is actually more of a judgement of how you use the power. A battery is very effective when most of the power is consumed in the evening. However, it’s not as beneficial when most of the power is consumed during the day with what the panels produce and it is fine to install the solar system first and then the battery to justify it with a better understanding of your power consumption.