Houses with solar that don’t also have energy storage like home batterieshave no way to use the excess electricity generated during the day when the sun is shining and solar energy is in abundance. When households have solar energy they can’t use, it goes back into the power grid.
Often, power companies pay households for giving back the extra power generated by solar, but not as much as they charge for the same amount of electricity later in the day, when people actually need it. Without a home battery, solar customers end up paying extra for the electricity they generated themselves, which is like paying the power company to store the energy for them so they can use it later. Instead of giving more money to the power companies, why not just store it yourself? With a home battery, solar households have this opportunity.
This eases the workload of power plants, decreases carbon emissions, and saves money for households with solar at the same time. Taking this into consideration, it’s hard to argue against Musk when he says that all solar panel owners need a home battery. Without a home battery to store excess electricity, solar owners continue to throw money and energy at the power companies. Home batteries keep electricity and money in the hands of the consumer.
This article comes from http://www.storagebattery-factory.com/news/Home-Batteries-Can-Save-More-M.html.