Electric Water Heaters and Demand Meter vs. Propane?

Weezbo

venilation of your home...

Kevin_in_Denver_2

Electric prices have been stable for 25+ years

My calculations are showing that I can save a lot of money with electric vs. propane or even natural gas if the price is over $.80 per therm. I'd have to go to demand billing. I've already verified that I can limit my home's highest electric demand for the month to about 6kW.

Without getting into all the assumptions and calculations just yet, do you guys know anyone that has recently tried this strategy?

I know this approach failed miserably in the early 80's. It was primarily because the homeowners refused to be inconvienced by load shedding, and often ran their demand up to 18kW and higher. But nowadays with a tight house, some window insulation and a properly sized hot water storage tank, 6kW of electricity used only at night would be sufficient.

A propane fireplace would be required for those rare design condition days. But hey, in the mountains you have to install at least one of those just for resale.

The savings on space heat and DHW is roughly 30% and bound to increase if the $/therm to $/kwh ratio keeps increasing like it has recently. Also, first cost is apt to be less.

Kevin_in_Denver_2

Electric prices have been stable for 25+ years

My calculations are showing that I can save a lot of money with electric vs. propane or even natural gas if the price is over $.80 per therm. I'd have to go to demand billing. I've already verified that I can limit my home's highest electric demand for the month to about 6kW.

Without getting into all the assumptions and calculations just yet, do you guys know anyone that has recently tried this strategy?

I know this approach failed miserably in the early 80's. It was primarily because the homeowners refused to be inconvienced by load shedding, and often ran their demand up to 18kW and higher. But nowadays with a tight house, some window insulation and a properly sized hot water storage tank, 6kW of electricity used only at night would be sufficient for heating.

A propane fireplace would be required in addition for those rare design condition days. But hey, in the mountains you have to install at least one of those just for resale.

The savings on space heat and DHW is roughly 30% and bound to increase if the $/therm to $/kwh ratio keeps increasing like it has recently. Also, first cost is apt to be less.

Nick Dearing

Electric vs. gas

I live in Northeast Ohio and for many years, electric has been cheaper than gas. I have lived in my home for about 11 years. Last year, I replaced my old 65% gas furnace with a new 96% one. My gas rate increased 35% so I am currently actually paying more with my new furnace than I did with my last one.(at old gas price) Our electric has only been going up 1-2%/year and our gas has increased at least 5-10%/year for the last 20 years. My gas water heater went about 6 months ago and I replaced it with electric. I switched to demand billing and my hot water costs alone droped from $35-40/month to $10-15/month. Currently our gas rates are about $1.50/therm and electric is about $1.05/therm here. I am installing radiant tubing in my floor this summer and putting in an electric boiler. Just as you said, I can hook it to an indirect and have most of my usage during the night. Also, this summer with the air conditioning, I saved about $50/month with demand billing. If it's cheap in your area, electric is the way to go! Clean, 100% efficient, no chance for CO, etc.

Kevin_in_Denver_2

A new controversy

Thanks for the information. Question: wouldn't electric water heaters make more sense than an electric boiler? They're cheaper and have some of the storage you need in order to use electricity at night and heat during the day.

Dale

Water heater vs boiler

Unless you went to a commercial water heater with sequencer the problem is that with a 5500watt element max to be switched on at one time the btu input is 18,800 btu max.( The on at one time part is so you and the neighbors on your transformer don't have the lights dim too much) If that is enough then the water heater will work. For most houses it isn't enough at design (newer 3bdr track houses where I live have heat losses of about 40K) and a boiler that has a sequencer to stage the elements is the way to go especially if setback is desired. I think the way things will go is more insulation with air to air heat exchangers for health reasons. As to demand meters the way to make sure you save money is to use lockout relays for non demand times. The 12 inch thick new basement concrete floor is a great way to do this if you're builing a new house.

Kevin_in_Denver_2

It's a passive solar SIP house. An HRV is planned that cycles based on the CO2 content of the air inside. I haven't found anyone yet that has a clue how to install that.