Think of your home as (small) profitable power plant

https://www.bostonglobe.com/2024/01/30/science/net-zero-home-renovation/

by _m_benjamin • 2 years ago

21 71 2 years ago

bostonglobe.com

_m_benjamin2• 2 years ago

Use federal incentives, spend USD $75k, money back in 6 years, then turn a small profit from then on. I need to move.

thoma4s• 2 years ago

https://archive.is/e1xN9

manfre• 2 years ago

I'm mostly curious about how a normal person can get a zero interest loan?

why_only_15• 2 years ago

I assume a government program for batteries, but not sure.

krallja• 2 years ago

Get the loan in 2019, with a generous markup on the product so you don’t notice the interest is baked into the price.

kylert• 2 years ago

Mass Save have various low or no interest loans available for improving energy efficiency and generating clean energy if you qualify for them. I used a Mass Save HEAT Loan about 10y ago to replace my old oil burning furnace with a gas furnace and paid zero interest. The new gas furnace had requirements on its efficiency.

While Mass Save sounds really generous, it's being funded by everyone in their electric bill. So in a way, you've already paid into the program. You might as well get something out by calling up a Mass Save auditor and seeing what you can get out of it.

ldoughty• 2 years ago

Credit cards were offering 0% interest for new customers for up to nearly 2 years (with good credit)

If I did a project like this, I certainly would max out a deal like that, and prioritize that payout over the duration.

If it was from a bank and 3+ years, I'd love to know how to do that too

M95D• 2 years ago

I wish I had my own roof.

PaulKeeble5• 2 years ago

Have a look for cooperative solar farm schemes. There might be a local one or a state/national one you can invest into to offset your electricity bill. There are more popular in the EU and UK but they are bound to come to the USA due to how cheap Solar is for power now.

bluescrn2• 2 years ago

In the same position. There's very few 'green tech' options for apartment dwellers.

It all has the prerequisite of owning a large and very expensive home. You need significant space for a solar(+battery) installation. Or for a heat pump.

Charging an EV at home requires you to have a garage or driveway, and we all know that public chargers are going to do a massive bait+switch, hiking prices way up once companies running them have established local monopolies and demand has built up.

Even a bike or e-scooter can be a pain to own without secure storage space if you've got to carry it up/down stairs each time you want to use it.

1234letshaveatw• 2 years ago

A large and very expensive home or... A cheap and small one works as well.

A garage or driveway or... a dirt 2 track also does the trick.

No need to overstate things.

_m_benjamin2• 2 years ago

I own my place but only the floor. I'm in a 2-unit condo, so I don't own the roof per se. That means if the guy upstairs has a toilet overflow, I get the downstream effects (that happened; not fun).

I wish I had a standalone home (floor to roof and all in between) - especially in an area where the retrofits from the article were possible. I've been 11 years in my current place and now I _really_ know what to look for next time.

I suppose it's like anything: once you've spent enough time to see how small cracks will widen; enough time to know what gutter configurations will cause; where the architecture might collect rain and cause flooding; where rodents can find ingress -- once you're pretty battle-worn, a new house shines different.

My wife is looking at places and because I've run maintenance, we look at things quite differently.

lucioperca2• 2 years ago

These suburbia homes are still pretty bad deal for the public. Lots of infrastructure cost come with them like car infrastructure etc.

some_random3• 2 years ago

As a society, we've decided that we want lots of infrastructure including car infrastructure.

dartos3• 2 years ago

Yknow, in the US, I think it was more auto industry lobbying in the 20th century that led us to the whole “stroads” situation we have.

People didn’t like having 3 lane roads right in their path to walk to the grocery store.

The municipal solution was to ensure everyone needed to drive everywhere.

jklinger4103• 2 years ago

Did we decide that in a vacuum? Like by some kind of super informed vote? Or did a system designed to maximize profits hide the downside, promote the upsides, and convince us to do it, to their financial benefit?

And now that it is the norm, are people defending it because they actually agree, or are they just afraid of change and too weak to fight it now that it is normal?

I notice bad ideas usually die with a few defenders, whose arguments can be summed up with "it just works for me" in the face of all evidence. Suburbs seem to be one of those concepts.

davemp• 2 years ago

It's only a bad deal if you ignore what a significant portion of the population prefers and value space lowly. There's more to life than optimal efficiency.

eru• 2 years ago

Please read carefully: 'These suburbia homes are still pretty bad deal for the public.'

The original comment was carefully worded to avoid any statement about whether suburbia was a good or bad deal for the people who want to live there.

Similarly to how protectionism and subsidies can be a good deal for those people who benefit from them, but still be a bad deal for the public.

bluGill• 2 years ago

That infrastructure is amortized over many years and so it is pretty cheap. Every time I look I discover the dense cities where you would think costs are lower end up having higher tax rates. Remember the original streetcar suburbs were built before electric, water/sewer and other services, they have all added that infrastructure over the years and replaced their roads many times.

Sure transit is cheaper than roads (and suburb costs don't count the cost of a car, while transit counts those costs), but roads are not that expensive over the lifetime.

bluescrn2• 2 years ago

Yes, if we all lived in city-centre 'WFH pods' eating bug paste we could get infrastructure costs and environmental impact way down! Then we could breed more humans, and 'growth' continues! (for some definitions of 'growth')

But while some (young) people are fine with super-dense urban living, not needing a car, and rarely leaving their city, many people place a very high value on space, peace+quiet, and the increased freedom to travel that cars offer.

the_gastropod2• 2 years ago

Interestingly, I’m not particularly young (approaching 40), and can’t stand living in the suburbs (where I moved, from a city, last year). I feel so completely trapped, unfree, and dependent on my car, it’s ridiculous. I’ll be eating a $40k+ loss on this house purchase to move back asap, and it will be worth it.

I find the ability to walk to my library or grocery store infinitely more freeing than having to buckle in to my car and drive to my destination. I like being able to hop on my bicycle and get out of the city, without having to navigate suburban style 45mph stroads. I like the actual peace and quiet as opposed to the leaf blower brigade firing up at 7am. This suburban lifestyle ain’t for me.

jklinger4103• 2 years ago

Reductio ad absurdum, straw man, slippery slope, bad faith. C-C-C-Combo breaker!

eitally• 2 years ago

A lot of these [expensive] incentives are already being wound down, and the ones under control of utilities (e.g. net metering) can radically impact the ROI of things like solar installations. It'll be interesting to see how things stabilize in California over the next few years now that new residential solar doesn't make sense for almost anyone [unless they also have batteries and drive EVs, since electricity is now more expensive than running most gas-powered cars].

Additionally, why would most homeowners spend this kind of money when the vast majority of people only stay in a give house for ~7 years total? The incentives are great, but I don't see substantial changes happening unless it becomes a true no-brainer to replace fossil fuel systems and inefficient infrastructure (windows, roofs, insulation) with updated materiel. Blowing in more insulation is cheap and easy, but most Americans don't have a rainy day fund that would make replacing a furnace with heat pumps something they casually decide makes sense... or gas appliances with electric, or a new roof, etc.

hattmall3• 2 years ago

75,000 in savings over 6 years is $12,500 a year, which means this person's utility bills were over $1000 a month!? I know that my house is wildly inefficient and $300-$400 a month is the worst it gets with extreme weather.

Talking with friends and family my bills are higher than normal, most are around $200 and less in the milder months. A quick search shows $469 being average us Utility bills and that includes water, trash and internet.

I would also like to know, what size the panels and battery are as well.

PaulKeeble5• 2 years ago

Typically a panel these days is going to be around 400W, so the 33 panels is likely somewhere around 13KWp. I am not sure which Needham (Boston?) they are referring to but in Boston would produce annually about 15 MW/h.

As to the battery the price gives us an idea of its size, $23,000 dollars. On the expensive side with a Tesla powerwall you get 13.5KW/h for about $9000, its possible to get about 2/3 that price with other systems. So somewhere in the region of 40-50KW/h of storage.

Hope that helps.

simonjgreen2• 2 years ago

Presumably the export has been factored in to this, so making money not just saving

PH95VuimJjqBqy• 2 years ago

I know that my house is wildly inefficient and $300-$400 a month is the worst it gets with extreme weather.

I lived in a house for 4-5 years where it struggled to stay cool in the summer and the bills would get up to $300-$400 a month as well.

One year I had an HVAC guy out to clean my unit and I was asking him questions (which I did every year) and this was the first guy to tell me when he generally sees issues like that it's insulation related.

He climbed up into my attic and recommended I add more insulation. I did so and the relief was shocking.

Obviously I understand how insulation can help but what shocked me was just how large a difference more insulation helped in a house that already had insulation.

Lessson learned that many times us technical folks know but don't truly understand. Every other HVAC person had just said the unit was on the small side.

So you may take a look at the insulation in the house, even something as laying more insulation in your attic may help tremendously.

Cthulhu_• 2 years ago

I know in my country (NL) modern houses are built to an energy efficiency standard, so that 15 odd year old houses like mine are pretty efficient and well-insulated; how is that in the US?

Over here if you have an older house you can get subsidies or attractive mortgage rates if you spend it on improving your house's energy efficiency, it's worthwhile looking for schemes like that.

Actually I should look into that myself; I don't need to improve insulation, but switching to electric heating and adding solar panels and a heat pump would be interesting, especially given we need air conditioning during the hottest periods nowadays.

hattmall3• 2 years ago

Yep, insulation is huge, my house has practically none. There isn't even an attic to put it in. On very hot days I have sprayed the roof and apparently a mister system will work extremely well.

technotarek2• 2 years ago

One man’s experience in DC (where the SRECs are crazy valuable):

Installed 10Mwh system in 2021 for ~$40k.

After federal tax credits, SREC earnings, reductions in electric bills, and payments from electric co for over production, we have $7k left to recoup in only 3 years. And that ignores savings from the gas we’re not spending on charging the PHEV.

I know it’s a luxury to have, but there’s also some pride value (clearly!). Fortunate circumstance if you’re in the right place and have the cash. I wish the investment was more broadly accessible.

djaychela• 2 years ago

10MWh?

simonjgreen2• 2 years ago

Surely 10 kWh

robin_reala• 2 years ago

Presumably KWh? That’d be ~25 rather than ~25,000 panels.

PaulKeeble5• 2 years ago

Could be an annual measure of expected output.

sumtechguy• 2 years ago

I have a 7k system. In 4 months since I have installed I have made about 3MW? Would have been more but ... winter. Maybe that is what they mean?

technotarek2• 2 years ago

Sorry, yes 10KWh!

PaulKeeble5• 2 years ago

Solar and batteries pays off pretty quickly and can bring you to a net zero position on electrical needs fairly easily (excess sold in summer, importing in the winter). On an annual basis I now power half of another home in addition to my own. If I take the total expected output over 25 years my electricity cost is 1/4 of what it would be from the grid per KW/h. I went 6 months last year importing almost nothing from the grid.

In the UK at least batteries and an inverter are actually quicker to pay off using an economy 7 electricity tariff since power overnight is less than half the price of during the day and is typically from Wind power and imported Nuclear from France. That can pay off in less than 4 years and will last 10-15 with li-po.

If you don't have a roof to put solar on then there are some cooperative schemes where you can own part of a solar/wind installation and still save on your bill. A national one is https://rippleenergy.com/ but there may be more local schemes that you could help fund and get the payback from, residents are banding together to build solar farms all over the country.

The big energy companies have messed up this transition to green energy terribly and its considerably cheaper to make your own power than buy from them, which lets be honest it shouldn't be.

midasuni5• 2 years ago

I’ve been wondering about just battery and inverter and using an agile tariff. How large an inverter did you get and what happens at full load (oven, kettle, electric shower and hairdryer all on at same time) which is presumably combined higher than the inverter?

PaulKeeble5• 2 years ago

My inverter is 3.6KW and can put out 4KW to the home. There is a normal limit for 3.6 in the UK for max export unless you do a more complex DNO99 application so that is the typical values. Above that you pull from the grid for the excess. I can run the oven (1.5KW) and kettle (2KW) but not a hair drier in addition. You change your behaviour a little with these solutions, you put the washing and dishwasher on when you have excess power or do them at night when it's cheap,you wait for the kettle to finish before hair drying. But the price isn't really driven by these rare combined events anyway, they don't matter in the grand scheme of things as most of your needs get met by the inverter and batteries.

ComputerGuru2• 2 years ago

To me, the obvious reason why solar would be a gamble is that I have no guarantee I’ll be living here in the same home five years - let alone twenty - from now and I can’t take it with me when/if I move.

zie• 2 years ago

If you don't think you will be living there in 5 years, you probably shouldn't have bought the place, as the up to 10% or more transaction costs will eat you alive.

ComputerGuru2• 2 years ago

In five more years, not "for five years."

midasuni5• 2 years ago

As a buyer I would value an existing solar/battery system, especially one with actual generation data, thus would pay more

blagie5• 2 years ago

My problem is whenever I've seen these numbers, they were completely baked.

"The total price tag for the entire home project was roughly $75,000, after rebates. But Tuttelman says it will pay for itself in about six years through energy cost savings."

The costs seem right. I've priced this. The savings are nonsense. I don't spend $75k in utility bills in six years.

"Other benefits include the stress savings of not having to guess when a furnace, which typically lasts about 15 years, is on its last legs."

My boiler is going strong after forty years, and the technician who looked at it last said this was typical and there's no reason to think it won't last another forty. I periodically need to replace a control board, which I should learn to do myself. In contrast, the system described -- with heat pumps, solar, and whatnot, has a lot more parts and things to go wrong.

I'm equally sceptical of the current direct environmental benefit. If I e.g. tossed out my gas-powered car and bought a Tesla, I'd have the environmental cost of manufacturing a Tesla. That would need to be lower than the environmental cost of the gas I'll use for the rest of the life of my car. I don't think it is.

There are reasons to buy this stuff (e.g. to support the green industry). That doesn't excuse the propaganda and the fake numbers.

ljf4• 2 years ago

Agree on some points here - in the UK I spend about £300 combined on gas and electricity.

But your boiler sounds interesting - if it is 40 years old it will be wildly inefficient compared to boilers from the last few years - on changing our 10yo boiler we saved about £100 a month across the year - But I only expect that boiler to last 10 to 15 years - but that is OK, by then I'm sure I'll be moving to electric heating and hot water, as I can only assume gas will be phased out.

blagie5• 2 years ago

I'm not quite sure how a boiler can be efficient or inefficient. It seems like for every watt of power going in, I get one watt of heat out. That's basic thermodynamics. If heat doesn't make it into the water, it still ultimately heats my house.

Perhaps language issue?

My boiler heats the water for my radiators which heat my house. That's not the same as my hot water tank, which heats running hot water. Here, where modern ones do tend to leak less heat into the air, and these do have a limited lifespan as the tank corrodes.

Can you explain? I feel like the only way I could go up in efficiency is if I sucked in heat from the outdoors with a heat pump.

ProllyInfamous• 2 years ago

I recently replaced an electric instahot (on-demand) water heater with a tank hybrid heater. In addition to dehumidifying and cooling the basement, it uses about a quarter of the electricity (from 10%, monthly, to 3% kWH).

During the winter, I keep the tub water plugged up for the heat pump to re-absorb... REDUCE, re-use, recycle, generate.

brk2• 2 years ago

I've done these calculations, particularly after putting an 11.6Kw solar array on our last house, which was in St. Petersburg, FL, one of the sunniest places in the US.

We sold the house after having the system for ~6.5 years, but we were tracking for a 9 year ROI. My cost was ~$23K out of pocket at the time, with power bills of $500-$800/mo., depending on time of year. I think our average daily consumption was 69Kwh, and the system produced the majority of that most days.

Assuming an average power bill of $600/mo., $23K would cover roughly 3 years of power bills. However, if the money was invested in a decent-ish portfolio, it would be earning some interest along the way, which could stretch what it covers to 5+ years. Anyway, when I did all the math, the solar panels never really made money, but what they did was smooth out our monthly expenses and gave some hedge against rate increases.

The new house is the same general area, and our use is about the same, but going to wait to see if solar takes a bigger decrease in cost before doing another array. It's mostly maintenance-free, but I did not output decline when the panels got dirty, and one panel died about 1 year after installation (and by then the installer company had gone out of business).

friend_and_foe• 2 years ago

I'm curious, it boggles my mind how people get energy bills that high. Do you pay 90¢ a kilowatt hour or something? What are you doing in your house to use that much electricity?

brk2• 2 years ago

In the previous house we had 3 A/C units for the house (4T, 4T, 1T), and two on the boat (1.3T, 1.3T) that ran pretty consistently. That was the vast majority of the consumption.

We had an electric clothes dryer, which would run a few hours a week. And electric oven and cooktop, which had minimal use (mostly cook outdoors). The only other large loads were an electric water heater and an elevator, plus a few PCs that were on 24/7.

Think of your home as (small) profitable power plant

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