Off the Urban Grid

Gas vs. Solar Water Heaters, Cost Comparison

Many of us would love to install a large solar panel system that produces enough energy to allow us to be independent of the municipal power grid, at least most of the year.  It’s a big, expensive undertaking though, so if you’re on the fence, you might consider starting with a solar hot water heater.

Though solar hot water heaters are initially more expensive to install than gas water heaters, they can save you quite a bit of money in the long run.  Let’s compare costs:

Gas vs. Solar Hot Water Heater Costs

Initial purchase prices: Gas (65 gallons) $590, Solar $7,000

Life expectancy: Gas 12 years, solar 40 years

Total equipment costs for 40 years: Gas $4,275, Solar $12,781 (based on 3.5% inflation)

Fuel costs for 40 years: Gas $46,428, Solar $16,250 (based on 6% annual increase in fuel)

Maintenance costs for 40 years: Gas $1,000, Solar $2,033 (based on 3.5% inflation)

Total costs for a gas water heater over 40 years: $52,293

Total costs for a solar water heater over 40 years: $38,064

Your savings for going with solar: $14,229.

These numbers are based on a “Gas vs. Solar: Compare Costs” chart in the August 2009 issue of Mother Earth News.

Their assumptions:

“The solar water-heating system initially uses the existing water heater as backup and provides 65 percent of hot water. The average family currently spends $300 annually to heat water. Maintenance of the solar system currently costs $24 annually. Fuel costs will increase by 6 percent annually. Other costs will increase by 3.5 percent annually.”

As you can see, solar is more expensive to install and maintain, but the payoff comes in lower energy costs over the long run.