Solar Energy FAQ: Will I Have Power When the Sun Goes Down?

Solar energy systems function by capturing the sun’s light and converting it into usable electricity. So what happens when the sun isn’t shining?

At night and on cloudy days, homes and businesses relying on photovoltaic energy can still use cost-effective power. Here’s how.

Grid-Tied Residential Solar Panels

If your solar energy system is connected to the traditional utility grid, you will have no worries about power when the sun goes down.

The grid is like a bank for this type of photovoltaic system, and you can draw on it whenever you need to. In fact, withdrawals are automatic. In other words, the grid kicks in and you automatically get electricity for your home or business at times when your system is not producing energy.

Most grid-tied customers are even able to make deposits into the grid storage bank through a process known as net metering.

If your system captures energy in excess of what you need (many do), that excess is fed into the grid for all electricity customers to share. But, because your equipment produced that power, the utility company pays or credits you for all of the solar energy you supply to the grid.

So when you need to use power from the utility company, those costs are offset!

Off-Grid Solar Systems

If your photovoltaic system is not connected to the grid, however, you need an alternative way to provide electricity at night and during bad-weather days.

A battery backup system is the answer to this conundrum.

With a battery bank, you can store up to several days’ worth of solar power or more, depending upon the size of your backup system. To determine a size for your battery, consider your average electrical usage and how often your area has unfavorable weather conditions. Experts recommend consulting a solar energy expert to ensure that you choose an appropriate size and configuration.

Instead of a battery backup — or, in addition to one — many off-grid customers choose to purchase a generator. If you decide on a generator, you can choose from a solar model or opt for a more traditional version.

If you choose the latter, you must keep a supply of propane, natural gas or diesel on hand to keep it powered when necessary. The only problem here is, in case of a natural disaster or national crisis, those fuel supplies may be impossible to maintain.

Alternatives for Storage

Some companies are looking into different solutions for storing the sun’s energy. One of the newest and most promising methods involves solar thermal technology.

Solar thermal power produces electricity by using the heat of the sun to boil water. The energy is then stored in salt, which can be heated to provide electricity when the sun isn’t shining.

In cold climates, a pressurized glycol system is the most effective solar thermal option.

Today, Intermountain Wind & Solar is proud to provide PV systems and other types of alternative power generating equipment to our customers throughout Utah, Nevada, Wyoming, Idaho and Montana. Contact us today to learn more about how solar energy can save you money.