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Thoughts about fossil free regs

hot_rod
hot_rod Member Posts: 22,022
So you build your dream home, spent the cash to make it very energy efficient, got the loads down to 10 btu/ sq ft. Expecting to pay peanuts for you gas.

The NAHB current poll of 4000 homeowners show energy efficiency has moved to the very top of the list.

You connect to the NG source and get your first heating bill. Basically the less your home uses, the more it could end up costing. Look at the actual fuel consumed, vs the varying cost and the fees!

Obviously the utility needs to cover operating costs, sock away cash to replace exploding, dated underground and infrastructure :) but you feel like you are getting over (fee-d)

This type of bill happens with electricity also. This is why consumers look at net zero and consider producing their own energy via PV or a PV buy in. They want some control over their energy future.

What would it cost to run an A2WHP for this load?
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream
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Comments

  • mattmia2
    mattmia2 Member Posts: 9,574
    It looks like $20 is all that isn't based on usage.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    edited March 2020
    Burn another type of fuel.

    I honestly have no experience with NG, but I really hate being tied to a utility.

    Electric (HP) isnt the only alternative.

    Is that equal to 175,000 btu total?
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Tim Potter
    Tim Potter Member Posts: 273
    ccf = 103,600 btu x 175 = 18,130,000 btu (according to google)
    Winter Park, CO & Arvada, CO
    Solid_Fuel_Man
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    The dream home isn't really the problem, in my opinion. If I were to build one today -- which I wouldn't, but that's another story -- it would have a net heating load of zero. No heat pumps, no boiler. Probably not even a fan anywhere. No PV required. Can it be done? Yes. I've done it. There really isn't that good an excuse not to. That leaves the two other areas which our ancestors used heat for: cooking and light, plus in most situations water. Light can be handled with LED lights at a remarkably small amount of power, so PV (or maybe a wind turbine?) for that. In some areas water can be managed with a windmill (yes, they are still made) and elevated storage. That leaves cooking (and refrigeration). Probably LP for cooking, and PV for the refrigeration compressors, although there are LP refrigerators made, too.

    So... how far off grid do you want to go?

    No, the problem with all the work on ridding us of fossil fuels for home consumption is not the new construction. It is the truly vast quantity of already built construction. Who is going to come up with the money -- for it comes down to money -- to convert all that existing built inventory to whatever flavour of renewable energy might become available? Not that it can't be done -- when I was teaching engineering some decades back, I used to point out to students that given enough money you can engineer almost anything you want. But... who, exactly, pays? Folks, somebody is going to have to pick up the tab -- and it isn't going to be cheap.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • mattmia2
    mattmia2 Member Posts: 9,574
    An induction cook top is as responsive of not more responsive than gas. The only caveat is that you can only use ferromagnetic cookware. That is what I would go with if I were trying to avoid fossil fuel.
  • hot_rod
    hot_rod Member Posts: 22,022

    The dream home isn't really the problem, in my opinion. If I were to build one today -- which I wouldn't, but that's another story -- it would have a net heating load of zero. No heat pumps, no boiler. Probably not even a fan anywhere. No PV required. Can it be done? Yes. I've done it. There really isn't that good an excuse not to. That leaves the two other areas which our ancestors used heat for: cooking and light, plus in most situations water. Light can be handled with LED lights at a remarkably small amount of power, so PV (or maybe a wind turbine?) for that. In some areas water can be managed with a windmill (yes, they are still made) and elevated storage. That leaves cooking (and refrigeration). Probably LP for cooking, and PV for the refrigeration compressors, although there are LP refrigerators made, too.

    So... how far off grid do you want to go?

    No, the problem with all the work on ridding us of fossil fuels for home consumption is not the new construction. It is the truly vast quantity of already built construction. Who is going to come up with the money -- for it comes down to money -- to convert all that existing built inventory to whatever flavour of renewable energy might become available? Not that it can't be done -- when I was teaching engineering some decades back, I used to point out to students that given enough money you can engineer almost anything you want. But... who, exactly, pays? Folks, somebody is going to have to pick up the tab -- and it isn't going to be cheap.

    I agree with you, only I would change the word problem to challenge. I have hope your students and their students are upon to the task, it's their future now.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Gordy
    Gordy Member Posts: 9,546
    edited March 2020
    That’s a hefty NG bill. 175 ccf for 32 days. 1 ccf is 103,600 btus. Basically 566,563 btus for 24 hours on average. 5.6 therms a day.

    Fossil free limits you to wind,hydro,and solar.

    The cost to get to net zero is exuberant.
    What’s the ROI, to build, and implement a net zero platform?

    Solid_Fuel_ManGroundUp
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    I'm at less than 10btu/ft2 if my design temp is -10F (and not -35F).

    My energy bills are laughable. It was not particularly difficult, or expensive to get there with reasonable architecture. Not 500 rooflines with dormers and 30' ceilings etc.

    My sentiment about being connected to NG is just what you show. Ridiculous usage fees where you are penalized for low use. I get it, the infrastructure needs to be paid for etc. LP is the same way, the more you use the cheaper/unit it becomes. But with LP you can beat the system by owning your tank (a big one!).

    Or you can use an unregulated fuel like wood, pellets, etc. That way the small heat load means less work, and you can still buy bulk fuel and store it for a few years.

    Jamie is correct about the existing structures though, much more expensive to retrofit, so a less expensive heat source makes more economic sense.

    The main reason I see with energy use, old or new, is the lack of understanding or frankly the lack of care most builders put into building envelopes. There are old sieves and nee sieves alike.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
    Canucker
  • Gordy
    Gordy Member Posts: 9,546
    Yes @Solid_Fuel_Man you can get there with sacrifices ( to some) in architectural design.
    It is still more costly than conventional builds.
  • Gordy
    Gordy Member Posts: 9,546
    I do believe if you go the net zero route there should be far better perks/incentives at all levels to facilitate the ground work to get there.

    Mortgage
    Materials
    Systems
    Utilities
    Realestate tax


  • Gordy
    Gordy Member Posts: 9,546
    The path to net zero🤣
    ratio
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    Two items @Gordy mentions are particularly a problem with net zero, never mind true zero: mortgage and real estate tax (at least in the eastern states). A third, related to the mortgage actually, is the building codes. Both the building codes and the mortgage people usually, if not always, require an "adequate" heating system to be installed, even if you never use it. Mumble mumble. The real estate tax people regard a net zero or even more a true zero build to be a money spinner, and raise your taxes appropriately. Mumble mumble mumble.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Gordy
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,540
    > @Gordy said:
    > That’s a hefty NG bill. 175 ccf for 32 days. 1 ccf is 103,600 btus. Basically 566,563 btus for 24 hours on average. 5.6 therms a day.
    >
    > Fossil free limits you to wind,hydro,and solar.
    >
    > The cost to get to net zero is exuberant.
    > What’s the ROI, to build, and implement a net zero platform?

    You forgot biogas, biodiesel, renewable diesel.........
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    Actually I was talking about true zero, not net zero. Net zero is a very slippery concept. If all inputs are taken into account, neither biodiesel nor renewable diesel are. Biogas is an interesting one. It isn't net zero, either, really, but in the form of digester gas from anaerobic digesters it is a very good way to reduce greenhouse gasses in general, as using it converts methane -- a much more powerful greenhouse gas than carbon dioxide -- into carbon dioxide and water (mostly... some Sulphur dioxide, some nitrogen dioxide, but minor amounts). It has been used for decades at some wastewater treatment facilities, quite successfully (although it must be admitted that the digesters are finicky to operate -- and blow up now and then). Not practical for residential use, but practical for large agricultural operations as well as wastewater plants. Some landfills also produce enough methane to make its use practical.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Gordy
    Gordy Member Posts: 9,546

    > @Gordy said:

    > That’s a hefty NG bill. 175 ccf for 32 days. 1 ccf is 103,600 btus. Basically 566,563 btus for 24 hours on average. 5.6 therms a day.

    >

    > Fossil free limits you to wind,hydro,and solar.

    >

    > The cost to get to net zero is exuberant.

    > What’s the ROI, to build, and implement a net zero platform?



    You forgot biogas, biodiesel, renewable diesel.........

    True, but those do require fossil fuels at some point in the circle, as does just about everything else we touch.

  • hot_rod
    hot_rod Member Posts: 22,022
    Depends on where the "bio" part comes from. Raising beans or corn for fuel?? Taxpayer subsided?

    Fossil fuel is a non-reversible form of energy. There are emissions involved with any combustion process also. Needs to be trucked or piped.

    Electricity is more scalable, it can be generated at the site, sold back and forth, becomes instantly available to all once in the grid, storage options are becoming available. Heat pumps exceeding COP of 3, is that possible with any fossil fuel, 3 units out for every 1 unit consumed?

    The key is finding the best ways to generate and distribute the power. The grid can be scaled up easier and quicker compared to thousands of miles of old underground pipes.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Gordy
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    Residential is only 17% of natural gas use. 1/3 is electricity. But largest is industrial use. That’s where there is a larger ROI if it’s a goal to curb fossil fuel and overall energy use.

    I worked at several factories. Heat recovery was abysmal. The last was a brand new steel can plant. They did a horrible job recovering heat from ovens and dryers and spend a ton of energy on excess ventilation and space heating as a result.

    They were running cooling towers all winter while gas fired MAUs blasted away.

    A couple hot water coils (already had glycol in the cooling loop) would have gone a long way. Could have also preheated wash water in the RO water storage tank.

    But less than 3-5 year paybacks. They wanted 6-12 months.

    While residential we are satisfied with 10-20 year investments in enhanced home construction.
    Solid_Fuel_Man
  • hot_rod
    hot_rod Member Posts: 22,022
    mikeg2015 said:

    Residential is only 17% of natural gas use. 1/3 is electricity. But largest is industrial use. That’s where there is a larger ROI if it’s a goal to curb fossil fuel and overall energy use.



    I worked at several factories. Heat recovery was abysmal. The last was a brand new steel can plant. They did a horrible job recovering heat from ovens and dryers and spend a ton of energy on excess ventilation and space heating as a result.



    They were running cooling towers all winter while gas fired MAUs blasted away.



    A couple hot water coils (already had glycol in the cooling loop) would have gone a long way. Could have also preheated wash water in the RO water storage tank.



    But less than 3-5 year paybacks. They wanted 6-12 months.



    While residential we are satisfied with 10-20 year investments in enhanced home construction.

    Data center server farms blow out 98% of the energy thy bring in. A Swiss server farm heats a swimming pool with the waste heat. One project in Finland heats 1000 homes with that energy. Amazons spheres in Seattle reuses the heat from servers.

    Low grade as far as temperature, but heat pumps could boost it up for industrial use.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    mikeg2015CLamb
  • Gordy
    Gordy Member Posts: 9,546
    Waste heat is a very much missed opportunity. It’s a nuisance, and mostly dealt with in such a manner.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Completely agree with the above posts about industrial waste! I simply cannot get my head around the extremely short payback they are only willing to go with.

    I understand the not wanting unnecessary complications or reduced output/increased downtime from energy recovery.

    I haven't told many yet, but I am about to change all of that. I'm building my own biomass processing plant/company. It wont just be about the simple paybacks. I see dead btu's everywhere!
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
    GordyGroundUp
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,273
    Hi @Solid_Fuel_Man , That sounds exciting! Please do keep us informed. Are you looking to make household sized units or something bigger? A hundred years ago Ruud made a trash burning water heater. As long as we can keep the air clean, it's still a good idea, probably more relevant now than ever.

    Yours, Larry
    Solid_Fuel_ManGordy
  • hot_rod
    hot_rod Member Posts: 22,022
    Sweden landfills 1% of their waste, recycle 49% and burn the rest for power. They actually import trash to fuel the boilers.

    Same basic technology used in Minneapolis, that trash burner provides power to around 25,000 homes. Most cities have plenty of trash to burn.

    It it can be burned as clean or cleaner than coal, it seems a better fuel than food stock, corn and beans, which are energy intensive to grow and process.

    Michigan imports waste from Canada to landfill around 9,770,385 cubic yards per year. It would be nice to turn some of that into energy instead of trash mountains which may end up as environmental cleanup sites one day.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    There are a number of waste to energy incinerators in the US, too. There is a problem, though: NIMBY. Getting permission to build one is next to impossible. I know -- I've tried. And gave up and designed a landfill for the jurisdiction in question instead.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • hot_rod
    hot_rod Member Posts: 22,022
    Site them where the landfills already are?

    Who are the NIMBYs in this case, certainly not going to be tree huggers fighting back.
    Pull the garbage from the oceans and power the people.

    Downtown Minneapolis has one right downtown for crying out loud :)

    Seems those big energy companies get and do pretty much what they want. They spend millions on TV ads promoting NG benefits, find a clever name for burning trash and market it like they do oil and gas.

    Maybe the energy climate has change enough to try this concept again? Electricity and district energy from these plants may be viable as both boomers and millennials are looking to cluster near cities and prefer townhouse/ apartment living to individual homeownership now a days. Plus I could sell a lot of energy/ BTU meters.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Solid_Fuel_Man
  • Gsmith
    Gsmith Member Posts: 431
    Waste to energy in the US is currently economically impossible even if the site was free and politically unopposed, the revenue from the energy produced cannot pay back the capital and operating costs even if amortized over 50 years unfortunately. They are practically impossible to finance. I believe only one Or two WTE boilerS have been added to any WTE plants in the past 25 years or so and those were tack on boilers to existing plants that had all the other common elements already in place (receiving pit, cranes, scales, roadways, stack, etc). Great idea but not economical in today’s environment as compared to the cost of landfills. And customers have voted that they won’t pay a premium for longer term environmental stewardship.
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    The NIMBYs to whom I refer are folks concerned about air pollution from the boiler/incinerator. They do have a point. Unless the system Is operated and controlled very carefully, it's remarkably hard and certainly not cheap to get trash to burn at high enough temperatures to ensure complete conversion of anything that might be in it (which might be anything!) to straight oxides -- and then to make sure your fine particulates and nitrogen and Sulphur oxides are removed. There is also a legitimate concern about heavy metal oxides.

    To be reasonably successful they need a remarkably clean waste stream (good luck with that).
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Solid_Fuel_ManJean-David Beyer
  • mikeg2015
    mikeg2015 Member Posts: 1,194

    There are a number of waste to energy incinerators in the US, too. There is a problem, though: NIMBY. Getting permission to build one is next to impossible. I know -- I've tried. And gave up and designed a landfill for the jurisdiction in question instead.

    It;s interesting because in some economically depressed river towns in the Midwest, like I’m in, I think NIMBY is less of a concern and they’ve wellcome a industry that could create maybe 20-30 or so high paying skilled jobs.

    Thy built one of the largest ammonia fertilizer plants 30 miles north of here. There was some pushback form some a small town of about 100 people, bu overall it created much needed jobs.

    I;d support a well operated and regulated incinerator. Can;t be worse than 3 or 4 other industrial plants. Plenty of open land ot build it and a major North-South highway from St Louis ot Minneapolis that connects I-80 and I-70.

    I;ve also been wondering if Amazon or Walmart wold build a warehouse in the area for that reason. Rather than the much more expensive, overdeveloped and politically corrupt Chicago area.
  • hot_rod
    hot_rod Member Posts: 22,022
    At a Jack Stack seminar recently, he was doing some consulting work down south in an industrial plaza. Mostly tip up concrete commercial/ industrial buildings in the area. He noticed a large hoop style tent structure on one of the lots in the plaza, struck him as unusual.

    He watched a 40,000lb truck pull in one end. 20 minutes later a fleet of Amazon Sprinters peel out the other end. They throw up these "tent" type transfer facilities in a few weeks time. And now Amazon is also in the real estate business tying up these lots for future development.

    Nobody beats Amazon when it comes to moving "boxes" :)
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Solid_Fuel_Man
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Maine had at least 3 TOE plants that I know of. All have closed their doors. Not economically feasible, and there was a noticeable smell! I believe burning trash (for the most part) is a better solution than landfilling for all but the most toxic of stuff. It's just really difficult to weed that stuff out.

    The plant which I am in the process of designing will be for forestry and mill residuals. We had two 39 Mega Watt biomass generating facilities which both closed down last year and are being demolished as I type. I tried to buy one of them. Political stuff very deep.

    Each plant consumed 90 tons/hour of biomass when operating at capacity, I'm going to have a home for a portion of that now.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • CLamb
    CLamb Member Posts: 273

    Maine had at least 3 TOE plants that I know of. All have closed their doors. Not economically feasible, and there was a noticeable smell! I believe burning trash (for the most part) is a better solution than landfilling for all but the most toxic of stuff. It's just really difficult to weed that stuff out.

    Incineration generates carbon dioxide but landfill sequesters the carbon. Unless trash incineration produces less carbon dioxide than other options for energy production I would think landfill is better.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    But the question is if that sequestered carbon in the trash, is less or more than would be released by generating electricity some other way. I'm sure TOE is more, but how much I dont kmow.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,273
    Hello, Perhaps another question to ask is how this compares to burning fossil fuels.

    Yours, Larry
  • hot_rod
    hot_rod Member Posts: 22,022

    Hello, Perhaps another question to ask is how this compares to burning fossil fuels.

    Like coal

    Yours, Larry

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    There are very few good options for handling waste... by far the best is to reduce the amount of it as much as possible.

    Landfills don't produce carbon dioxide, true. What they do produce, though, is methane -- which is a far more potent greenhouse gas than carbon dioxide. Some of the bigger and best run landfills capture that methane with the upper cover, and burn it (mostly it's flared; once in a while it's used for heat or power -- but there's enough Sulphur in it to create some interesting problems). Most smaller ones just let the stuff go... There's also the little problem of leachate, which is supposed to be (and in better designed ones is) captured -- but then what? It's pretty horrible stuff. It can be treated...

    I can assure you from experience that designing, building, and maintaining a landfill isn't simply a matter of backing up to the creek and dumping any more!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Gordy
    Gordy Member Posts: 9,546
    This kind of touches on how the oil sands in Canada are not profitable until oil hits 50 dollars a barrel. I imagine they are scaling back about now.........


    But as far as landfill waste heat generation. It may never reach a profitable stand point, but rather be a way of controlling our waste. The balance may fall on the users someday. Both contributors of waste, and users of the waste heat to balance out the numbers.
  • PerryHolzman
    PerryHolzman Member Posts: 234
    The overall discussion about how to live and dispose of waste energy economical is very large and there are not a lot of easy answers when it comes to disposal of waste.

    However, to return to where the thread started on home energy usage. Even the best designs must allow for routine air exchange for healthy living. It's not only about minimizing leakage and more insulation.

    I have personally looked at using a ground based heat pump, solar only, solar with thermal battery to supply winter heat (store enough energy over the summer to heat the house during the winter - the "Thermal Battery" using phase change materials would cost about $100,000 to build - with a 100 year design life, not counting building a vault to place it and the cost of the solar system, etc.

    I looked at the cost of gutting the interior and insulating to modern standards (rewire at the same time) and then reinstalling my nice plaster walls.

    The fact is that none of those options by themselves or combined would have anything less than a 50 year payback (and some were over 100 years). Another reality: none would increase the value of my house more than a few thousand dollars either.

    OK, I have a house built in 1954 with 4" studs and 2" rockwool insulation (and reported 4-6" rockwool in the sealed attic - now that someone could look through a hole in the roof recently and tell me what was up there). The current design heating temperature is -15F (even though we almost always see -20 ever year and -30 every several years). The house is a bit cool on those -30F days. I believe when I modeled the heat loss I used -20F (my slant fin file got corrupted so I cannot tell anymore).

    What truly astounds me is the size of heating equipment being put into many of the newly constructed homes (admittedly larger homes) is the same size or larger... and all kinds of people tell me that their energy bills are higher than mine in my 1954 house.

    There is just no excuse for that. Their energy bills should be in the range of 1/2 of mine.

    A reality is that much of the energy conservation talk - is just that. Talk. Talk is the cheapest thing to do - it cost nothing if you do it right (no legal entanglements). It cost extra to actually do it and houses are almost always built as cheep as possible except for surface finish and fixtures for upscale houses so that it looks "premium."

    I believe that is our real problem. We have not yet implemented any system that hits contractors or homeowners in the wallet - hard - for inefficient construction, remodel, and use.

    In my opinion, the standards we have are minimal and largely meaningless if you cannot build a house twice the size of mine these days and clearly use much less energy than mine.

    Perry
  • ratio
    ratio Member Posts: 3,616
    'Efficiency", that's a socio-political term, not an engineering term.
  • Sal Santamaura
    Sal Santamaura Member Posts: 529
    ratio said:

    'Efficiency", that's a socio-political term, not an engineering term.

    I guess all those college engineering courses I took had it wrong then. Calculations too. Or I just imagined hearing / studying about it.
  • PerryHolzman
    PerryHolzman Member Posts: 234
    ratio said:

    'Efficiency", that's a socio-political term, not an engineering term.

    I'm also an engineer. Efficiency is a real thing. The way we sometimes talk about it in a public setting is often not exactly engineering efficiency; and I'll concede that "socio-political term" might be a good description of certain uses of the term.

    However, my key point about why are we not really building energy efficient homes and buildings these days stands. Why don't the standard require it and penalize both the contractors, businesses, and homeowners when they don't do it?

    Expanding that: Why are not businesses required to do energy efficiency upgrades that have reasonable paybacks for their industry and products?

    I also don't understand why there are not 40,000- 50,000 Btu max conventional heating boilers and mod/con heating boilers out there.

    Perry
    Jean-David Beyer
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    @PerryHolzman and @Sal Santamaura are right. Efficiency has a very specific meaning in thermodynamics. One aspect of which is that it is really applicable and usable only on closed, complete systems (and it really shouldn't be used for systems where the only output is thermal energy, by the way, but that gets off into the thermodynamic weeds, so let's not). It isn't applicable on bits and pieces of a system -- whether it's a boiler or funace in a house, or a carburetor on an engine, or whatever. But it is also used these days as a "feel good" sales label on bits and pieces of systems (was the 100 mile per gallon carburetor the first use of it that way? Hmm...) and that is also the sense in which it gets bandied about in political and regulatory circles.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England