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Re: Can this gas WH be replaced with electric?

Posted: Mon Jan 21, 2019 7:16 pm
by LTLFTcomposite
wwhitney wrote:I've not actually studied Article 220 in the NEC on load calculations, but I do know that almost always the optional method described in Part IV of the article (starting at 220.80) is almost always a lower number. So be sure your calculator is using the optional method. The result is still quite conservative.

Cheers, Wayne
As always thanks for the reply.

Yes, I got into the whole thing about the "optional method" and low and behold the answer on the spreadsheet came out at exactly 100A. That's using the commonly available 4500W heaters, not the 3800W. The only part I'm not sure I did right was the range... it says to use the nameplate rating, which I neglected to check. This is your garden variety electric range which apparently has a nameplate rating around 11-12kW but for whatever reason calculations commonly peg them at 8000W. I'm not sure which number I should be using in the optional method calculation. They say these can be installed on 40A circuits, so the 8000 number makes sense.

Re: Can this gas WH be replaced with electric?

Posted: Mon Jan 21, 2019 7:25 pm
by LTLFTcomposite
iPlug wrote:Consider a heat pump water heater...
GerryAZ wrote:I second the recommendation to get a heat pump type...
It would be nice, but that's an extra grand not laying around. This house is not high occupancy, payback would probably be three years minimum. More complex installation too, having to add the drain line.

We had a neat system at a house quite some time back - a heat recovery unit on the central AC unit. That thing made crazy hot water 9-10 months out of the year when we did even have the power turned on to the water heater. Surprised those never became more popular. If you think about it why have a second heat pump, you already have one! Purportedly made the AC more efficient but that's just theory.

Re: Can this gas WH be replaced with electric?

Posted: Mon Jan 21, 2019 8:13 pm
by Oilpan4
If the gas water heater is the only gas appliance I would get rid of it and turn off gas service if the person doesn't want additional gas appliances.

Re: Can this gas WH be replaced with electric?

Posted: Mon Jan 21, 2019 8:42 pm
by LTLFTcomposite
Oilpan4 wrote:If the gas water heater is the only gas appliance I would get rid of it and turn off gas service if the person doesn't want additional gas appliances.
That's the idea... simplify things, outsource the combustion of natural gas to the power company.

Re: Can this gas WH be replaced with electric?

Posted: Tue Jan 22, 2019 2:37 am
by Oilpan4
I said no to natural gas.
Natural gas is a great thing and hydraulic fracturing made it possible reduce the pollution put off by power generation by eliminating coal fired power plants.
For me it was all about the $, the surcharge out on the coop is high.
Imo it's not worth the install cost which would run around $2,000 unless I also at installed a gas furnace, gas water heater, gas dryer, gas range.
So total cost would be up around $7,000 if I did all the appliance change overs my self.
I would have to have a contractor licensed gas certified plumber pull permits to do the initial install to the house. Can't get around that part.

Re: Can this gas WH be replaced with electric?

Posted: Tue Jan 22, 2019 3:02 am
by LeftieBiker
Natural gas is a great thing and hydraulic fracturing made it possible reduce the pollution put off by power generation by eliminating coal fired power plants.
Replacing it with contaminated wells and even whole aquifers. This is why I'm pushing for us to get a ground source heatpump instead of a dual air-source/NG heating system.

Re: Can this gas WH be replaced with electric?

Posted: Tue Jan 22, 2019 3:37 am
by Oilpan4
Where?
I have only ever been able to find a hand full cases of contaminated ground water due to fracking.
Not bad considering nearly a million fracking jobs have been completed.
I live in a fracking heavy area and have an excellent water well.

If the fracking boom that started in the mid 2000s, that was extended by the fracking ban scare all through the Obama administration years never happened then natural gas would probably cost around $12 to $20 per million BTUs. Making it prohibitively expensive for most power generation.
The Natural gas power generation market share would have shrank to almost nothing and coal would still make nearly half our nations electricity.

The ground source geothermal is nice I would like to do it.
But first I have a water well and rain water system to install to eliminate my $55 per month coop water bill.
And put up solar panels.
While planting an orchard.

Re: Can this gas WH be replaced with electric?

Posted: Tue Jan 22, 2019 3:59 am
by LeftieBiker

Re: Can this gas WH be replaced with electric?

Posted: Tue Jan 22, 2019 4:47 am
by LTLFTcomposite
The power company is going to do what the power company is going to do, but lately that appears to be increasing renewables in the mix. If we put in another gas water heater that fossil fuel consumption will be "locked in" to the mix.
Really switching from a gas to an electric water heater is no different from switching to an EV from an ICE other than maybe the scale. Oh sure, there will be the trolls saying now we're heating water with coal, but if you ascribe to the greening grid theory it still should be a better way to go.

Re: Can this gas WH be replaced with electric?

Posted: Tue Jan 22, 2019 9:23 am
by stjohnh
I considered a heat pump WH to replace our gas unit a year or so ago. Energy costs seemed about the same or even a little lower with the heat pump. BUT... I checked around and repairs for a heat pump unit are relatively frequent (most gas or resistance electric units never need service in their 10 year typical life span). And, when a heat pump WH needs fixing, repairs are typically expensive. The idea is great, but I think manufacturers need to increase reliability for widespread heat pump adoption to occur.