Converting from Natural Gas to Electric

[ryanho87]

What are some potential downside to converting from a natural gas heater to electric?

I just moved into a house with a pool and Solar Panels (not a solar pool heater). After living here for a month, I've heated the pool/hot tub 4 times and ended up incurring a $160 gas bill from doing that which seems kind of high to me. Since my solar panels are currently generating more electric power we consume (119 excess kWh last month), I think it might make sense for me to convert to an electric heater.

I'm mainly looking to be able to heat the spa (~400 gallons) up a few times a month and am not looking to maintain a higher temperature for my pool.

 

[ajw22]

How many BTUs is your gas heater?

Downside of a HP is it will heat your spa slower and may not heat it at all as air temperature falls into the 50s.

Gas is a better on demand heater. HP is a better maintain a given temperature heater.

Use your gas heater for only heating your spa like you say the HP will be used and the gas bill will be a lot lower. You have a sunken cost with your existing gas heater. Only heat your spa for a month or two and see what the gas bill is. Then figure out how many months it will take to break even on the HP cost.

 

[ryanho87]

I've done some research and I don't think I'd be looking at a heat pump since those seem to be geared more towards maintaining a higher overall temp in the pool. I'm more looking at on demand heating just for my spa. I found a few electric heaters that resemble tankless water heaters. Maybe something like this Raypak. Does anyone have any experience with these for on demand heating?

 

[ajw22]

See page 6 in http://cdn.globalimageserver.com/FetchDocument.aspx?ID=909a39c1-286c-4f11-95ef-6ab5b4db1829

Can you give the heater 200 amps of electrical service?

 

[ryanho87]

Not currently, but I'll be upgrading the electrical in my house for a Kitchen remodel, so I could definitely add this if it made sense.

 

[Tres Gatos]

A typical gas heater (400K BTU) will heat a regular size spa about 1 degree/minute. Assuming you are bringing the water up from 70 to 100 degrees it will take about 30 minutes with a gas heater. The Raypack (27KW 92K BTU) will take over 4 times as long almost 2 hours. So after 2 uses you will zero out your monthly banked electricity. Is it worth the investment?