Can A Solar Water Heater Work At Night?

March 09, 2015

Since solar water heaters require the sun to heat water, you may be wondering if they can provide you with hot water at night.

The answer: Yes, they can!

Here’s how.

Solar water panels on roof of Florida home

Solar water heater usually systems come with a backup unit

The solar water heater system is usually paired with a backup gas or electric water heater, which has 2 purposes:

  1. Heat up water on days that don’t provide enough (or no) sunlight.
  2. Augment heating the water in case it’s not hot enough.

So, if the water isn’t hot enough when you need it at night, the backup unit helps out. You’ll always have hot water no matter what it’s like outside.

“What’s the point of a solar water heater if I need a backup unit?”

Well, the gas or electric backup unit should barely run at all. The heated water is stored in a well-insulated tank, preventing the water from cooling down too much before it’s used.

The backup unit just adds a bit of supplemental heat to keep the water at a comfortable temperature.

Overall, you’ll save 70% to 90% on your water heating bill using a solar water heating system.

According to Florida Solar Energy Center, a family of 4 using a solar water heater with a backup element could save $200-$300 a year in lower water heating costs.

“Is a solar water heater worth it in the long run in Florida?”

Long story short: yes.

In our previous article on solar water heater costs and savings, we determined that by taking advantage of federal and local rebates, a solar water heater easily pays for itself in the long run—and then some.

A solar water heater lives about 20 years. So, the family of four could save $4,000 to $6,000 over the solar water heater’s lifetime.

So, let’s do the math:
$7000 to purchase & install solar water heater (average cost, rounded up)
-$1000 (FPL rebate)
-$1800 (30% federal tax credit)
-$6000 (high end of energy savings)
-$1800 (amount of money saved overall)

Also, since a gas and electric or gas water heater only lives about 10 years and solar water heater lives about 20 years, a solar water heater could also save you the amount it would cost to buy a whole new gas or electric water heater.

Of course, these are all just estimates. Actual costs and savings depend on your home and family’s needs.

Want to find out how much a solar water heater could save you? Contact Plumbing Today for help.

Plumbing Today provides award-winning plumbing service in Florida with locations in Sarasota, Tampa, Orlando, and Naples.

Posted in: Buyer's Guide

Related Reading