Rural New Hampshire - starting from scratch

[chrisstratton]

Hello helpful people!

I just sold my DIY solar camper after 2 years. You guys were great in helping me design and execute that. 1740 solar on roof, 3000 Growatt, 24v150ah LifFePO4, 12k btuh heat pump. That system ran the A/C and fridge almost 24/7 for the two years.

So - I'm coming back to the well again. We bought a small property in Rural NH and are seeking a permit now. Basically, it is a one bedroom, w/ full basement. I have a wide range of questions and I value your opinions and am requesting them.

Desired design - 720 SF Cottage, slant roof

Bad Idea?
Does anyone have any idea if an off grid powered property has a diminished or enhance re-sale value? What about snow clearing in NH off the panels? Is that a big deal. Basically thinking to have no grid tie option - no power from the grid.

Permitting
1) Does anyone have any leads on resources regarding land owner restrictions so I can bone up on those, namely, where does a registered electrician come in on a self built, stand alone house? I'd like a builder to frame, insulate, drywall, roof, exterior (windows, etc), and perhaps rough wiring and plumbing. Not sure of sequence of approvals (this is in Washington NH) - I realize the question is way out there, but you guys are great, and someone here might actually know and be willing to help. Would love to hear others experiences of new construction off grid in New England

Down to more common questions
2) Well pump. Presumably 180' ish well w/ submerged pump? Which pump to get? or soft start? or pump and holding tank and another pump?

3) Hot water heater - should I bother w/ those super efficient, super expensive heat pump ones?

4) My thought is about 7kw PV panels on the roof, and a Growatt | 8kW Split Phase Off-Grid Inverter, plus a propane backup generator of about 7kw. And perhaps 48V Lithium Battery 120Ah 6 kWh LFP. Does this seem reasonable? What about automatic switch-over? I saw some discussion about C and NO and wonder about practical results of whatever that is to fire up and release the generator.

5) Heatpump. I figure a regular efficiency heatpump for A/C and some heating, with a backup of either a pellet stove or propane in the basement. Probably propane. I am thinking to setup for easy winterization and maybe going that route for Dec-March. Thoughts?

 

[Johneb]

You might want to think minisplit instead of heat pump for that small space.

 

[chrisstratton]

Yes, sorry, I meant a mini split heat pump

 

[Madcodger]

We're building another house in Maine (over about 2-3 years - just got the excavation work and septic done last week, pouring pad in spring). I looked at similar designs to the one you posted (which looks great). Not to dissuade you too much re that, but that amount of glass proved problematic to my thoughts of a house powered mostly by solar (or really any house that doesn't cost a fortune to heat, even with a bit of passive gain). We want to power as much as possible with solar (hopefully make it net zero). But to do that, with even the most efficient mini split, we found that holding onto that heat is essential. We're planning R40 (actually about R43) walls, using a double stud wall with dense pack cellulose (trying to avoid foam if possible). Even with triple pane windows that have a U-factor of 0.12 to 0.15, that's the equivalent of about R7, and about the best you can possibly do for glass in a home. So, a very huge heat loss no matter how good the window. Just something to think about, but in our case, we changed the design and reduced the glazing (glass) considerably, just to hold onto the heat.

I also loved the idea of solar panels on a slant roof, until I thought about snow. The angle on that roof looks to be about a 4:12, or just over 18 degrees (maybe 6:12?). I am fairly sure that will hold snow for many days, or even weeks, cutting your solar production to almost nothing. I have some panels on a heated outbuilding with a 6:12 pitch (almost 27 degrees) but I can reach those panels with a snow rake. If I don't, I can't get much solar production. During winter in NH, you will have less than 4-5 hours/day of decent sun anyway (we're down to about 3.5 hours/day in late December). Personally, I'm now looking at possible ground mounts even with a 10/12 pitch on the new house, as ice can really cut production, too, when it forms on the bottom of panels.

Anyway, I hate to be negative at all, but these might be some things to consider, for a solar home in New England.

Re: permitting, go talk to your local code enforcement officer, asap. In my area, they really care about plumbing and septic, but hardly look at electric and framing. I prefer that because I've done a lot of both and will almost certainly exceed code, but this REALLY varies by town in the three most northern NE states. I would also start looking for a builder asap, because every decent one in our area is booked into next year and charging record high prices. I finally decided to be my own general contractor because I don't need to hurry to build this house, but the labor shortage is also the big reason we're taking so long to build it.

Finally (for my initial comment) you asked about things like heat pump water heaters. Oh, heck, yeah. Look at state and federal rebates and tax credits on anything that saves energy, and by the time you also figure in your lower operating costs, I find them to be a no brainer. We are admittedly trying to use no fossil fuels in this house except for a propane emergency backup generator (cheaper than MANY days of battery), but even if you consider propane a heat pump water heater can make sense as an alternative.

 

[chrisstratton]

We're building another house in Maine (over about 2-3 years - just got the excavation work and septic done last week, pouring pad in spring). I looked at similar designs to the one you posted (which looks great). Not to dissuade you too much re that, but that amount of glass proved problematic to my thoughts of a house powered mostly by solar (or really any house that doesn't cost a fortune to heat, even with a bit of passive gain). We want to power as much as possible with solar (hopefully make it net zero). But to do that, with even the most efficient mini split, we found that holding onto that heat is essential. We're planning R40 (actually about R43) walls, using a double stud wall with dense pack cellulose (trying to avoid foam if possible). Even with triple pane windows that have a U-factor of 0.12 to 0.15, that's the equivalent of about R7, and about the best you can possibly do for glass in a home. So, a very huge heat loss no matter how good the window. Just something to think about, but in our case, we changed the design and reduced the glazing (glass) considerably, just to hold onto the heat.

I also loved the idea of solar panels on a slant roof, until I thought about snow. The angle on that roof looks to be about a 4:12, or just over 18 degrees (maybe 6:12?). I am fairly sure that will hold snow for many days, or even weeks, cutting your solar production to almost nothing. I have some panels on a heated outbuilding with a 6:12 pitch (almost 27 degrees) but I can reach those panels with a snow rake. If I don't, I can't get much solar production. During winter in NH, you will have less than 4-5 hours/day of decent sun anyway (we're down to about 3.5 hours/day in late December). Personally, I'm now looking at possible ground mounts even with a 10/12 pitch on the new house, as ice can really cut production, too, when it forms on the bottom of panels.

Anyway, I hate to be negative at all, but these might be some things to consider, for a solar home in New England.

Re: permitting, go talk to your local code enforcement officer, asap. In my area, they really care about plumbing and septic, but hardly look at electric and framing. I prefer that because I've done a lot of both and will almost certainly exceed code, but this REALLY varies by town in the three most northern NE states. I would also start looking for a builder asap, because every decent one in our area is booked into next year and charging record high prices. I finally decided to be my own general contractor because I don't need to hurry to build this house, but the labor shortage is also the big reason we're taking so long to build it.

Finally (for my initial comment) you asked about things like heat pump water heaters. Oh, heck, yeah. Look at state and federal rebates and tax credits on anything that saves energy, and by the time you also figure in your lower operating costs, I find them to be a no brainer. We are admittedly trying to use no fossil fuels in this house except for a propane emergency backup generator (cheaper than MANY days of battery), but even if you consider propane a heat pump water heater can make sense as an alternative.

Thank you! The tip about a water heater is what I was hoping to hear about that. Lots of great suggestions in your response. Thank you

 

[DIYrich]

With a minisplit, you will need a backup heat source for NH. Geothermal can be oversized for the coldest nights. Insulated well. Don't know if you can drill the well under the foundation to save space. Combined sump pump pit, radon mitigation, and geothermal well? Also provides hot water.

 

[Madcodger]

With a minisplit, you will need a backup heat source for NH. Geothermal can be oversized for the coldest nights. Insulated well. Don't know if you can drill the well under the foundation to save space. Combined sump pump pit, radon mitigation, and geothermal well? Also provides hot water.

I must respectfully disagree with @DIYrich on this issue. In years past, an air-air heat pumps could not perform well in NE winters. But now, for a reasonably well-insulated home, we find they perform just fine here in Maine. We simply don't get enough days of below zero temps to make them have to work all that hard for days on end, and many newer units maintain heating capability down to -14F, and as I recall some can now heat down to -22F. Our coldest night last year was -17F and the news people were all a-flutter about the cold temps, but that lasted just a few hours. One of our units is rated down to just 5F but it doesn't shut off at that temp, and has maintained heat in that building at well below zero. The other, rated down to -14F, didn't blink. I have switched to other heat sources based purely on cost during cold spells, but it was not at all necessary and was done because those sources were sitting there from years past in those buildings, unused. And when I went back and did the math, I probably didn't save much when I did that, even temporarily. Efficiency of heat pumps in cold temps is much less than at higher temps, certainly, but it's still over 100% (most heat pumps are about 300% for much of the year, with a Coefficient of Performance of 3:1 or more).

As for geothermal, I know Rich loves it, but in my opinion it rarely makes economic sense these days unless it's easy (cheap) to install the ground loop AND you are sure you are going to remain in the building for a very long time (as much as 20 years). Well drilling is expensive in New England, and air-water heat pump equipment costs more than air-air. With the improvements in air-air heat pumps (especially inverter mini splits), geothermal is quickly loosing its attractiveness. If you design a building with good water barriers, air barriers, vapor barriers, and thermal barriers (in that order), it doesn't take nearly as much energy to maintain a good indoor environment compared to years past. Air-air heat pumps can perform beautifully in New England as long as you have power, in a building with reasonable insulation.

Backup heat sources are always a good idea, but not because the primary heat source is an air-air heat pump. The reason for a backup is that things break, often at inconvenient times. But that's true for any heat source.

 

[rhino]

Which pump to get?

Look at grundfos pumps. Have soft start built-in and very efficient.

 

[rhino]

What about snow clearing in NH off the panels?

Can you ground mount the array? A tilt-able ground mount can let you angle the array at 60 degrees or so in winter and snow will tend to slide off especially if you used bifacials.

 

[darkskies]

Living in NH for many years, and having had two houses with solar panels (pro installed), I can chime in on a few things (mostly reinforcing what others have said).

RE: Electrical. You can check with town, but I think most allow homeowner to do electrical, as long as they get permits and follow code.

RE: Roof. You roof looks fairly low slope, so snow would be an issue. I've had steep roofs (10:12 and 11:12) and after about a day, the snow would slide off. Granted, it then creates 2-3x the depth of hard packed snow on the ground and that can be an issue. One house had a deck on back, which guests usually used as an entrance, is it was easy access from driveway. Well, it would get tons of snow that was hard to keep clear, due to solar panels two stories up, dropping snow.

RE: Production. Depending on your orientation and shading, I get 5-6 hours of production at the best times of year, 3.5-4 hours at the worst times. May and June are the best months for me, mostly because consumption is low, and very high production. July-August generate a lot, but consumption is very high.

RE: Heat. Mini split we have for a basement room now, works really well, and works with it -10 F or so. Hasn't been an issue working the two years we've had it so far. I'm not sure of the draw for A/C, but our main A/C, off of a propane fueled furnace with A/C unit, will show about 4-5kW, when compressor is running for A/C. We've got about 2200 sq ft. Conventional furnaces/boiler systems will easily handle heating needs, though.

RE: Well. It's a crap shoot as to how far you have to go for water. My last house started with 2 gpm at 400 ft (fracked), and over a few years, dropped to about .75 gpm. Had another well drilled on other side of house, they went 405 ft (no fracking), and I was getting 12-15 gpm. New house in a different area has about 1 gpm and is over 400 ft.

RE: Generator. We have a 10kw Generac. Works well, though are using an ATS currently, as our SolarEdge system with BackupInterface doesn't have firmware support yet for handling the generator (but has the hardware to handle it). A note on fuel. Propane is pretty expensive in NH. We get a great deal, because we are in a large rural development, where the propane companies offer group deals. At my old house, it was VERY expensive, and generators do consume quite a bit.

RE: Grid Tie: I know you mentioned off-grid, but it you do grid tie, you loose about 30% of the produced energy, when consuming (IOW I have to generate 30% more to break even).

 

[G00SE]

A ducted heat pump is essentially a giant mini split no? It was my understanding minisplits are also heat pumps (at least the ones that can do more than cool)
Is the benefit (outside of ductwork) simply the inverter inside?

 

[Oldphile]

As a new solar adapter in NH, I'll add my 2 cents regarding snow. I have a 6;12 pitch roof. Typically snow easily slides off as soon as the sun shines. Most of the panels are very close to the eaves. That really helps create an avalanche.

 

[Browse]

Didn't know there were so many members from NH. I'm considering retiring to New Hampshire within the next few years but I'm not sure which part of the state would be best. I'd like to set up a decent sized solar array and we're looking for at least 2 acres, preferably more. The biggest limiting factor for us is that we want natural gas for heating and cooking. Having access to municipal water would also be good because we want an in-ground pool, but usually living closer to large towns and cities is going to limit lot size. We took a trip a few years back and went through Bedford, up to the lakes and mountain region then over to Portsmouth during the week long trip. Bedford was nice but houses and property taxes are as expensive as NY (or more). I'm guessing we'll be limited to the southeast part of the state if we want to get all of these things. Does that sound right?

 

[rhino]

we want natural gas

That does infer you'd be close enough to a population center that there are gas pipelines running to everyones house and therefore more expensive. Did you mean to say specifically natural gas or will propane be adequate as well? In which case your options are a lot larger. For what it's worth we cook on electric during summer (hot plates and small convection oven) when there is plenty of excess power and in winter heat with a real wood stove designed for 24/7 use and cooking.

 

[Browse]

Never really liked the idea of relying on the filling of propane tanks. The cost is also higher. A pool heater running on propane would be astronomical.

 

[darkskies]

Never really liked the idea of relying on the filling of propane tanks. The cost is also higher. A pool heater running on propane would be astronomical.

Natural gas limits you to being very close to the cities and acreage will be $$$. Propane is more expensive, but most places have 500 gallon tanks (so 400 gallons), so filling is less frequent. We fill about 4-5x a year. This year, we are locked in at $2/gallon.

I know some people who have used solar for pool heating to help with costs. Not sure about the details.

If you go propane, you have much more flexibility in location, and can pick locations with more land, at a better price point (typically, the farther North, the cheaper).

The other question is whether you want to be nearer to civilization. If you go farther North the land and homes are less, but you'll be farther from stores, malls, hospitals, theaters and other entertainment venues. A good or bad thing, based on your goals.

Lastly, although things are easing, homes/lots are scarce and prices are still very high.

 

[houseofancients]

Never really liked the idea of relying on the filling of propane tanks. The cost is also higher. A pool heater running on propane would be astronomical.

I'd go all electric ( already did that myself in north west Europe ), using air/ground to water heat pumps to support a few heatpump mini splits.

As an added fallback you could add a wood burning stove/waterheater.
Reasoning is pretty simple : electricity I can generate myself.

It is impractical here to go fully off-grid all year round due to cloud cover during november/december so have a grid connection, but that is used for a Max of 30 days per year, and due to net metering and a pretty big system I can send power I cannot use or store back in summer, leaving the bill usually 0.

As the grid is extremely stable here, it really doesn't make sense to use a generator , as it would need to be pretty big, and don't want to depend on gas ( rather gas pricing)

 

[PreppenWolf]

Ground mount the panels to allow snow clearing unless you're doing a very steep roof and will add coils to melt ice build up. The fall and early spring snow is notorious for ice layering and will not melt/slide off panels. I'm in SE NH and every house I see with roof panels is getting basically zero solar Jan-April.

Also on temps we've had -34F in SE NH about 12 years ago. Once you get to 10F mini-splits are not going to be an efficient solution. Go wood heat and solar AC. Save the power. We're heating our 2000sqft house on 3-5 cords a year. And you get the keep the house as hot as you want.

 

[chrisstratton]

Thanks, Everyone. Much to consider.