my new shop radiant, so far

hot_rod

I'm skipping the glycol and running constant circulation on the slab loops. The thermostat basically opens the 3 way ZV to the boiler. With a small Alpha I could use a hefty computer back up for power outages. I also have a generator.

I'm using some Pyrex piping to observe air and dirt for demo and teaching.

The Caleffi 106 is a 3 way valve, installed on the Sep 4. A control with an outdoor sensor diverts from A2WHP to boiler when outdoor temperature drops the heat pump COP.
A dual version can divert directly from HP or a buffer tank.

Although I don't have a HP yet. If anyone has a spare 3 ton, send it my way

JakeCK

I would love to have a a2whp heating a buffer tank and just use my gas boiler for the really cold days... 

Keep the updates coming on how well it works.

hot_rod

A friend just paid $4.80 for LP in upstate NY, on his "automatic fill" program. So 61 bucks /MMbtu to run his old 85% FA system.

With his KWH cost at .13 his new A2WHP running at 2.6 cop will cost around 15 bucks/ MMbtu.

Yes his distribution system is designed for low temperature SWT, that is the key to 2.6 COP.

It will be interesting to see where fossil fuel costs end up this season.

JakeCK

Pair that with solar pv and... lol giant middle finger to the PUCO's

hot_rod

JakeCK said:

Pair that with solar pv and... lol giant middle finger to the PUCO's

Yep, I have 6 kw so far

JakeCK

I went all out and maxed out what I could conceivably do with the roof space I have on a city lot. 14kw DC, 42 panels between the front slope of the house, and both sides of the garage. Enphase micro-inverters. Also upgraded the service from 100amp to 200amp to allow for the conversion of gas appliances to electric over time. I was considering going to 400 amp but decided against it. I have a feeling at some point in the not to distant future when we are all driving EV's I might regret that decision.

My goal is making this 92 year old house net zero, if possible. Maybe by the time it's 100.

hot_rod

I went with a SMA Sunny Boy inverter
In a power outage it has 2000 W available. If the sun is shining of course.

Zman

Most grid-tied inverters will not run unless they have grid power to synch up with. Did you find a workaround?

hot_rod

Zman said:

Most grid-tied inverters will not run unless they have grid power to synch up with. Did you find a workaround?

here is how it works, the installation company adds a receptacle right at the inverter, SMA approved hack. One other mod would be to run that receptacle inside to be a little more convenient. Although it may never get used, power is fairly stable the locals tell me, although rolling brownouts have been discussed. The power utility is pushing battery storage systems. The catch being they can pull from the homeowners batteries if needed. https://www.thesolarnerd.com/blog/sma-sunnyboy-inverters/