can concrete radiant floor heat be substituted for storage?

[amh]

yeah.. do a search for PVwatts. good calculator. I was running about 10percent over this fall. Had EPIC snow this winter, so I've been blanked out a while. weather is 30 year average in their calculations.

The company I bought from did an estimate for me. Guy on the roof, camera and GPS.. they can show you the path of the sun every month of the year. Very cool for them to figure out shading issues.

It won't work for everyone.. but it might be a good solution if you like the heat pump. Maybe that, coupled with the wood stove for the coldest few months (or as a nice, no power needed solution for outages)

JP

Thx jp11 and bob? Never thought of that.
can u tell me more on what i would have to do to offset the cost.
jus see how many watts im using in the winter compared to the rest of the year?
then do tje calculator?
whats the initial investment, rough guest?

 

[JP11]

You'd need to see how much power you're using all year.
Then go to the pvwatts website and put in the array size you need. For example.. I use about 1200 kWh per month. So I put in 14kw for array size (it's a bit under that for usage, but it was a round number to start. Also.. the 'rated' power isn't really the output. I have two 5k inverters.. so in full sun it puts out just slightly over rated power..10100 watts or so)

Much of the payback comes down to what your state's laws are. Your state gets an A grade for net metering laws.. so you're likely in very good shape there.

The next issue is how many square feet of south facing roof you have. If you don't have room for the panels, it's kind of a moot point.

My cost was 2.50 per watt. prior to the 30% back from the government.

If you were going to do it.. you'd aim to get rid of your power bill completely. If you were planning to use your heat pump MORE than current.. you'd need to size your array larger than the sum of your past electric bills.

When I installed mine.. I added 6 panels over what the solar company recommended. I knew I had another air handler and AC unit to add this summer... that, and I may want an electric car for my wife. So it was just easter to tack on more capacity right from the start.

JP

 

[Mike Fromme]

I wouldn't rule out the boiler.

The main reason for storage is to keep the boiler running at max efficiency. Being able to extract heat from water storage at a controlled rate is a nice secondary benefit.

If you use an air handler for the main floor the eko can be plumbed to heat that area first. When there is no call for heat upstairs you can dump the excess into the slab. Which keeps the boiler running for the full burn.

The basement would get hot and keep the upstairs warm until you fire the boiler again. There will be some temp swings. But probably not a whole lot different then your current setup of running a woodstove in the basement.

It won't be as simple as water storage to keep your house at a stable temp. And there'd be a lot of trial and error on when to fire and how much to load based on the outdoor temp. But the boiler wouldn't care as long as it doesn't idle often.