Any hope for a 1980s all-eletric home in Massachusetts?

[RMD]

I'm considering purchasing a home in Norfolk, MA (02056). The home was built in the early 80s, and the builders thought they were being smart by making the entire home 100% electric heating. It uses electric baseboards for the most part, coupled with a handful of air sourced mini-split systems. The home is quite large (4600+ sqft), and the heating in the winter is brutal. Utility bills show an *average* of $723/month - which is at about 16.5 cents/KwH. There are months (Jan/Feb) that the electrical costs shoot above $1600/month and 9800 KwH!

I really love this home and want to make it work, but there is no way I'm going to be willing to eat that kind of utility bill. We've looked at other, new construction homes that are similar in size and cost $200/month to heat with natural gas at the height of winter!

The cost to retrofit an oil furnace (no natural gas available) would be very, very large as there is no existing radiant or baseboard piping, nor are there any ducts and there isn't much room for them either. Plus, the idea of spending tens of thousands to install oil heat really rubs me the wrong way! So I REALLY want to make solar work. This is my "forever" home, so I'm willing to drop a good chunk at the beginning to ensure long-term return on my investment. I'm even researching ground sourced heat pumps - which costs a TON of money.

Alas, living in New England makes this seem tough. A 10Kw system would likely only kick $2000/year off this bill. Nothing to shake a stick at, but if I can go bigger and live with a longer term payoff, I'd like to. My concern is that I *think* MA limits net metering to 10Kw and smaller systems. So if I go bigger, I think I'd lose net metering. As my only hope is to oversize the system and generate large excess during the 4-5 months a year we get good sun, I'm having trouble making the numbers work. (Plenty of southern facing roof space, by the way. Probably 2000sqft or more.)

But MA also does SRECs, which seems like that could make things viable. If I install a 20Kw system, even with the loss of net metering, I'd produce about 24 SRECs annually which each selling for about $285 - that alone would offset most of my electrical costs. Alas, this goes down over the course of 10 years - so at the end of that 10 year period, I'm in some trouble without net metering. (Although even a 20Kw system seemingly would only produce an excess of about 3800 Kwh/year - which is only about $645! Most of the year, I'm still way below my needs as the biggest draw is during winter.)

Anyway - sorry for the long post. I just really want to make this place work. Any advice or help is greatly appreciated. I'm looking into stuff like adding more mini-splits (newer ones can work fairly well all the way down to 0 deg F), and even spray foam retrofits. But I want to attack this from both ends - efficiency and renewable sources.

[bcroe]

I'm considering purchasing a home in Norfolk, MA (02056). The home was built in the early 80s, and the builders thought they were being smart by making the entire home 100% electric heating. It uses electric baseboards for the most part, coupled with a handful of air sourced mini-split systems. The home is quite large (4600+ sqft), and the heating in the winter is brutal. Utility bills show an *average* of $723/month - which is at about 16.9 cents/KwH. There are months (Jan/Feb) that the electrical costs shoot above $1600/month and 9800 KwH!

I really love this home and want to make it work, but there is no way I'm going to be willing to eat that kind of utility bill. We've looked at other, new construction homes that are similar in size and cost $200/month to heat with natural gas at the height of winter!

The cost to retrofit an oil furnace (no natural gas available) would be very, very large as there is no existing radiant or baseboard piping, nor are there any ducts and there isn't much room for them either. Plus, the idea of spending tens of thousands to install oil heat really rubs me the wrong way! So I REALLY want to make solar work. This is my "forever" home, so I'm willing to drop a good chunk at the beginning to ensure long-term return on my investment. I'm even researching ground sourced heat pumps - which costs a TON of money.

Alas, living in New England makes this seem tough. A 10Kw system would likely only kick $2000/year off this bill. Nothing to shake a stick at, but if I can go bigger and live with a longer term payoff, I'd like to. My concern is that I *think* MA limits net metering to 10Kw and smaller systems. So if I go bigger, I think I'd lose net metering. As my only hope is to oversize the system and generate large excess during the 4-5 months a year we get good sun, I'm having trouble making the numbers work. (Plenty of southern facing roof space, by the way. Probably 2000sqft or more.)

But MA also does SRECs, which seems like that could make things viable. If I install a 20Kw system, even with the loss of net metering, I'd produce about 24 SRECs annually which each selling for about $285 - that alone would offset most of my electrical costs. Alas, this goes down over the course of 10 years - so at the end of that 10 year period, I'm in some trouble without net metering. (Although even a 20Kw system seemingly would only produce an excess of about 3800 Kwh/year - which is only about $645! Most of the year, I'm still way below my needs as the biggest draw is during winter.)

Anyway - sorry for the long post. I just really want to make this place work. Any advice or help is greatly appreciated. I'm looking into stuff like adding more mini-splits (newer ones can work fairly well all the way down to 0 deg F), and even spray foam retrofits. But I want to attack this from both ends - efficiency and renewable sources.

I'm in a 1978 all electric home here in NW ILL. It was subsequently converted to a high efficiency
propane furnace, much cheaper but not as good as natural gas. Aside from the usual conservation
things like tons of added insulation, a buried sink high tech heat pump would be a good bet. Yes more
costly initially, but they can save year round. No place for ducts, isn't there a basement? That leaves
the mini splits, but they may switch over to the expensive resistance heat just when its really cold.
An alternative would be to switch over to propane instead; buy a big enough tank so a summer fill
up will get through the whole winter.

Rules here in the Wild West are less restrictive, I bank 13,000 KWH in summer and just make it
through the winter for free. Bruce Roe

[RMD]

I'm in a 1978 all electric home here in NW ILL. It was subsequently converted to a high efficiency
propane furnace, much cheaper but not as good as natural gas. Aside from the usual conservation
things like tons of added insulation, a buried sink high tech heat pump would be a good bet. Yes more
costly initially, but they can save year round. No place for ducts, isn't there a basement? That leaves
the mini splits, but they may switch over to the expensive resistance heat just when its really cold.
An alternative would be to switch over to propane instead; buy a big enough tank so a summer fill
up will get through the whole winter.

Rules here in the Wild West are less restrictive, I bank 13,000 KWH in summer and just make it
through the winter for free. Bruce Roe

Alas, no basement. The home is built on a knoll which is on top of a solid stone ledge. (We want to add a pool too - so THAT will be interesting.) There is a small propane tank for cooking right now, but plenty of room to add a larger tank. Alas, with no basement, I'd have to really screw up the look of the home with bulkheads for ducts. Probably a no-go.

You're banking 13k KWH during the summer!? How big is your system? I've been using PVWatts to estimate output, and a 10Kw system doesn't even cover summer time air conditioner usage - except in August:

Month 	/ KWH 	/ Cost 	/ Solar Output 	/ Net / Cost with Solar
Jan	9729	$1,621	731		8998		$1,485
Feb	9411	$1,605	671		8740		$1,442
Mar	7915	$1,351	1180		6735		$1,111
Apr	5201	$890	1361		3840		$634
May	2797	$481	1124		1673		$276
Jun	1559	$245	1152		407		$67
Jul	1563	$258	1244		319		$53
Aug	1105	$185	1321		-216		-$36
Sep	1315	$219	1003		312		$51
Oct	1474	$235	736		738		$122
Nov	3966	$617	641		3325		$549
Dec	7010	$1,086	556		6454		$1,065

[bcroe]

My Sq Ft is close to yours, except half is the basement. Probably a lot less loss.
Your summer KWH are huge; mine are negligible. Think about more insulation and a
geo thermal heat pump. It saves 12 months. A 97% propane furnace will only solve
winter problems, though that might be enough. Your consumption is double the KWH
I make every year. You would need an acre of panels to produce that kind of power.
I add up 53,045 KWH consumed, 11,720 KWH to be generated by 10KW PV.

My panels are on the ground, which gives a lot more options. I think your projected
PV production is low, because your clouds are a lot like mine. The PV system
here is limited to 15 KW. However I get extra energy out by extending the sun day
with extra panels facing the rising and setting sun. When its cloudy, the extra panels
all respond to the dispersed light, and bring up the minimum. However, I can't
claim overall to have a big advantage, just that I don't buy any electricity or propane.
Bruce Roe

[Carl_NH]

RMD.

Well I would have an energy audit done, then tighten up the house first, and add as much insulation as possible. Then look at the newer mini-split heat pumps.

Also with a crawl space, insulate the outside walls and also under the floor joists too.

As far as system size suggest you contact National Grid (or your supplier) - there may be a 15KW limit - but I see Class 1 Facilities can go up to 60KW.

For you 2000SF roof area, that should easily fit 60 panels (40"x65" size) or so 300W panels would get you 18KW.

Carl

[RMD]

RMD.

Well I would have an energy audit done, then tighten up the house first, and add as much insulation as possible. Then look at the newer mini-split heat pumps.

Also with a crawl space, insulate the outside walls and also under the floor joists too.

As far as system size suggest you contact National Grid (or your supplier) - there may be a 15KW limit - but I see Class 1 Facilities can go up to 60KW.

For you 2000SF roof area, that should easily fit 60 panels (40"x65" size) or so 300W panels would get you 18KW.

Carl

Did a bit more research. It's definitely a 60 Kw limit. I believe I can potentially put in a 23 Kw system with my available roof area across 3 buildings! Really quick research suggests that the gross cost of something like this is upwards of $75k - but after tax rebates, it's closer to $55k. Without doing anything to reduce my power usage (which, obviously, I will), we're down from an average monthly bill of $732 down to only $361. That's less than my 1800 sqft condo. (Granted, it was built in 1840, but still Sold. Payback period is only 4 to 5 years. If I couple this with efforts to reduce consumption (like a fancy new mini-split that works at 100% capacity all the way down to 5 deg F), I might get down to net-zero!

[Samsolar]

But MA also does SRECs, which seems like that could make things viable. If I install a 20Kw system, even with the loss of net metering, I'd produce about 24 SRECs annually which each selling for about $285 - that alone would offset most of my electrical costs. .

I'm in NH and thought I'd be getting about $50/ SREC. (Have not gotten my first check yet) Is $285 a current number for MA? Seems high to me, especially long term. Anyone else have some thoughts on this?

[bcroe]

23 KW is only going to cover half your present consumption. Connecting that together on multiple
buildings could be complicated.

If you put PV on the ground, you will be able to keep the snow off and get the reduced energy of
winter. And making them tilt to vertical in the snow months only will reduce accumulation without
much impact on production. Bruce Roe

[RMD]

23 KW is only going to cover half your present production. Connecting that together on multiple
buildings could be complicated.

If you put PV on the ground, you will be able to keep the snow off and get the reduced energy of
winter. And making them tilt to vertical in the snow months only will reduce accumulation without
much impact on production. Bruce Roe

True, although I'm hoping to cut usage a substantial amount. The current owners seem to rely mostly on electric resistance heat almost entirely. As you can see from my numbers before, winter time usage accounts for about 75% of total consumption. That's the thing I need to attack. They have several mini-split systems in various rooms, but I believe (and I'm confirming) that the mini splits are somewhat older models that can't operate with any efficiency below freezing. In those scenarios, it reverts to electric resistance. I think that be replacing these, and added a couple more, I can get the winter time usage down by at least 30-40%. Summer time usage would also benefit by about 10% due to the increased AC efficiency.

Even with just a 17Kw array, the average bill would go from $732 to $363. So my dream of a net-zero may not be doable without ground based solar, but I'd be pretty happy with those utilities.

[emartin00]

I would look at installing a few mini split heat pumps. They are relatively inexpensive, and will be FAR cheaper to run than the baseboards. The other option is pellet stoves. Although wood pellet prices aren't great at the moment compared to oil. They're very easy to install, and maintenance is minimal most of the time.
Propane heat is typically the second most expensive option after electric heating, so it's not going to save you a ton of money.

What is your insulation level like? Do you have the ability to add more?

[RMD]

I would look at installing a few mini split heat pumps. They are relatively inexpensive, and will be FAR cheaper to run than the baseboards. The other option is pellet stoves. Although wood pellet prices aren't great at the moment compared to oil. They're very easy to install, and maintenance is minimal most of the time.
Propane heat is typically the second most expensive option after electric heating, so it's not going to save you a ton of money.

What is your insulation level like? Do you have the ability to add more?

The mini-splits will be our first order of business - assuming the current ones aren't new-ish models that can function at low temperatures.

I think one issue here is that, without a basement, the home is built directly on the slab. (I think.) That's one reason it's so hard to keep warm.

The current owners say they redid insulation as part of a 2010 renovation, but I've got no real info on that yet.

In terms of propane, at least in MA, propane is on-par with oil heating - and about half what it costs with electric baseboard.

[Alchete]

Wow, that electric bill is insane.

There's no central A/C or ductwork? Have you gotten any quotes on adding ductwork, as opposed to radiators? Electric heat is so inefficient, that I imagine if you run the numbers that any alternative (ductwork/forced hot air) will be cheaper than a $50K+ solar panel array...

With attic access, ductwork is easy to run to the 2nd floor, and can be run to the 1st floor via chases in closets, etc.

Also, get a real energy audit that uses a blower door test (not the joke energy audits that MA provides for free). It's entirely possible that heat is leaking out your attic from unsealed light fixtures, etc. (Air sealing an attic: https://www.youtube.com/watch?v=4_2PuilhlPc)

You could then get a much smaller solar system.

[RMD]

Wow, that electric bill is insane.

There's no central A/C or ductwork? Have you gotten any quotes on adding ductwork, as opposed to radiators? Electric heat is so inefficient, that I imagine if you run the numbers that any alternative (ductwork/forced hot air) will be cheaper than a $50K+ solar panel array...

With attic access, ductwork is easy to run to the 2nd floor, and can be run to the 1st floor via chases in closets, etc.

Also, get a real energy audit that uses a blower door test (not the joke energy audits that MA provides for free). It's entirely possible that heat is leaking out your attic from unsealed light fixtures, etc. (Air sealing an attic: https://www.youtube.com/watch?v=4_2PuilhlPc)

You could then get a much smaller solar system.

Little/no attic space. (It's cape style.) Yes, it may be cheaper short term to add a propane or oil furnace + ducting, but with incentives, long term it likely won't.

[emartin00]

Electric heat is so inefficient, that I imagine if you run the numbers that any alternative (ductwork/forced hot air) will be cheaper than a $50K+ solar panel array...

On the contrary, electric heat is nearly 100% efficient. It's just outrageously expensive with today's electric rates.

[bcroe]

Don't forget, a geo thermal heat pump will continue to be relatively efficient no matter how
cold the air is. The best air to air may continue to run below freezing, but the energy
multiplier will continue to drop approaching the same as resistance heat at some point.
Bruce Roe