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Zero energy ready homes are coming

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Re: Zero energy ready homes are coming

#301

Post by Bloating »

bluGill wrote: post #274
Johnny555 wrote: post #243

Earlier quoted context omitted.

If you can find a way to convince Americans they don't all need a yard that can easily fit 6 (japanese) houses, we'll be well on our way. I think we are on our way there, most new developments around here have houses that are nearly the size of the lot, with a tiny back yard and smaller front yard, and little room between houses. Developers get more money by making lots small and houses big, so there’s little incenti…

Most people don't use their yard. They don't have more than a few flowers in the garden. 20 minutes with a push mower is enjoyable exercise but they wouldn't want it to take longer.

I enjoy my yard, and my house. I do not like "city living". To each their own

Re: Zero energy ready homes are coming

#302

Post by bluGill »

smolder wrote: post #24
giantg2 wrote: post #2

Interesting. Is there a good consise page detailing the main differences between this and older standards? Stuff like cost and ease of maintenance comparisons?

To get really high R value on insulation, often that means a 2x6 or 2x8 framed outer wall to allow for the additional thickness needed by the insulation. Double pane windows are well-surpassed by those with many panes and carefully designed frames with low thermal bridging. Aside from more insulation you need great air sealing, across every joint and in every window and door frame. Older construction had no explicit…

Modern houses have gone back to 2x4 walls. Then the put 2 inches of foam under the siding so the thickness is equal to a 2x6. There is already on the market standard doors and windows that fit this. Though 4 inches of foam may make more sense yet, but there are no standard doors or windows for that thickness so costs go up.

Re: Zero energy ready homes are coming

#303

Post by bluGill »

ortusdux wrote: post #14
jabart wrote: post #8

Earlier quoted context omitted.

Things switched from insulating the wall cavity to insulating the outside of the house. Engineers started to factor in the insulation value of a 2x6 compared to the insulation it was next to and the heat loss in cold climates. Same applies for hot climates. Now these homes are being wrapped in insulation on the outside with all joints sealed, then insulated on the inside and essentially pressure tested for air leaks.…

Heat exchangers are a big one, but they are not yet that common in the US. They are used to pre-heat the makeup air. I'm looking into one atm as part of a HVAC upgrade as currently running a bath fan with all the windows closed will draw air down the chimney.

Heat exchangers have been code for more than 20 years. Maybe not common, but only because there are a lot of old houses. Or maybe where you live didn't adopt the new code?

Re: Zero energy ready homes are coming

#304

Post by boringg »

s1artibartfast wrote: post #245
coffeebeqn wrote: post #227

Earlier quoted context omitted.

What period of time is that kWh over?

kWh/kh :P That is to say, 7 cents per watt or 7 grand for a 10 KW array

Solar is typically quoted as $ / Watt.

For reference what you quoted was 0.7 $/Watt not 7 cents.

While the cost of the panels has dropped - you still have balance of system and, yes, the unbelievably high interconnection costs (location dependent)

Re: Zero energy ready homes are coming

#305

Post by jjav »

lotsofpulp wrote: post #251
jjav wrote: post #250

Earlier quoted context omitted.

> If you have to cross a 40ft+ road with vehicles traveling at 50mph (i.e. 40mph speed limit), I consider that not walkable. Ok, but that's a quite radical limitation to the definition of walkable. What is the reason to put up self-imposed limitations like that? I mean, by that definition even most of Manhattan wouldn't be called walkable even thought it's the most walkable city in the US! In my very suburban neighbo…

> What is the reason to put up self-imposed limitations like that? Because I have seen how risky it is to cross due to speeding drivers in large vehicles looking at their phones. It is a large distance to cross, and if someone is mobility impaired like an old person or handicapped or child, it can be quite harrowing. Also, NYC is completely different because the speed cars travel at is actually 25mph. A world of diff…

> NYC is completely different because the speed cars travel at is actually 25mph

Unless there's traffic jam, driving speeds in the 4+ lane avenues in Manhattan is certainly higher than 25mph. (Source: used to spend all my weekends in Manhattan so I've done a lot of walking and cycling all over it.)

> Even as a healthy young guy, I feel intimidated walking across 80ft+ of vehicles that can be traveling at high speeds.

You should not be crossing when cars are traveling at any speed other than zero, that's what the pedestrian crossing lights are for.

In any case, you're right in that if you set a personal limitation on what is walkable that excludes nearly every part of the country (including Manhattan), then you won't find any walkable areas.

Personally I don't mind crossing a street (with a red-light protected crossing) so I find suburban areas to very walkable since I can (and do) get to any stores I want within an easy walk.

Re: Zero energy ready homes are coming

#306

Post by lotsofpulp »

jjav wrote: post #305
lotsofpulp wrote: post #251

Earlier quoted context omitted.

> What is the reason to put up self-imposed limitations like that? Because I have seen how risky it is to cross due to speeding drivers in large vehicles looking at their phones. It is a large distance to cross, and if someone is mobility impaired like an old person or handicapped or child, it can be quite harrowing. Also, NYC is completely different because the speed cars travel at is actually 25mph. A world of diff…

> NYC is completely different because the speed cars travel at is actually 25mph Unless there's traffic jam, driving speeds in the 4+ lane avenues in Manhattan is certainly higher than 25mph. (Source: used to spend all my weekends in Manhattan so I've done a lot of walking and cycling all over it.) > Even as a healthy young guy, I feel intimidated walking across 80ft+ of vehicles that can be traveling at high speeds.…

>You should not be crossing when cars are traveling at any speed other than zero, that's what the pedestrian crossing lights are for.

You would never finish crossing then. Lots of times there are cars traveling in the lanes that are approaching the intersection, and you have no way of knowing if they are paying attention or not to the traffic lights.

At low speeds, you can eyeball them sufficiently decreasing their speed and confirm they are stopping, but at high speeds, it is impossible to tell.

Re: Zero energy ready homes are coming

#307

Post by westurner »

DoreenMichele wrote: post #208

Contrary to what I am seeing in comments on HN, this is not just for single family detached housing. If you go to the ZERH website, under Program Requirements it says: Versions 1 and 2, Single Family, Multifamily, and Manufactured Homes https://www.energy.gov/eere/buildings/zero-energy-ready-home... Additionally, one of the photos in the featured article has the following caption: Lopez Community Land Trust built thi…

Passive solar building design : https://en.wikipedia.org/wiki/Passive_solar_building_design#...

Low-energy house: https://en.wikipedia.org/wiki/Low-energy_house

List of low-energy building techniques: https://en.wikipedia.org/wiki/List_of_low-energy_building_te...

/? Passive solar home (tbm=isch image search) https://www.google.com/search?q=passive+solar+home&tbm=isch

/? Passive solar house: https://youtube.com/results?search_query=passive+solar+house

/? passive solar house: https://www.pinterest.com/search/pins/?q=passive%20solar%20h...

(Edit)

Maximum solar energy is on the equatorial side of the house.

Full-sun plants prefer maximum solar energy.

10ft (3m) underground it's about 75°F (24°C) all year. Geothermal systems leverage this. (Passive) Walipini greenhouses are partially or fully underground or in a hillside, but must also manage groundwater seepage and flooding; e.g. with a DC solar sump pump and/or drainage channels filled with rock.

Passive solar greenhouses (especially in China and now Canada) have a natural or mounded earthen wall thermal mass on one side, and they lower wool blankets over the upside-down wing airfoil -like transparent side at night and when it's too warm (with a ~4HP motor).

TIL an aquarium heater can heat a tank of water working as a thermal mass in a geodesic growing dome; which can be partially-buried or half-walled with preformed hempcrete block.

Round structures are typically more resilient to wind:

Shear stress > Beam shear: https://en.wikipedia.org/wiki/Shear_stress

Deformation (physics) > Strain > Shear strain: https://en.wikipedia.org/wiki/Deformation_(physics)#Shear_st...

GH topic: finite-element-analysis https://github.com/topics/finite-element-analysis

GH topic: structural-analysis: https://github.com/topics/structural-engineering https://github.com/topics/structural-analysis

What open source software is there for passive home design and zero-energy home design?

Round house: https://www.pinterest.com/search/pins/?q=round%20house

The shearing force due to wind on structures with corners (and passive rooflines) causes racking and compromise of structural integrity; round homes apparently fare best in hurricanes.

Re: Zero energy ready homes are coming

#308

Post by s1artibartfast »

boringg wrote: post #304
s1artibartfast wrote: post #245

Earlier quoted context omitted.

kWh/kh :P That is to say, 7 cents per watt or 7 grand for a 10 KW array

Solar is typically quoted as $ / Watt. For reference what you quoted was 0.7 $/Watt not 7 cents. While the cost of the panels has dropped - you still have balance of system and, yes, the unbelievably high interconnection costs (location dependent)

I totally agree and fixed it in the post you responded to. At the end of the day a panels and electronics are a minor contribution to the project cost.

I think in most of California it is still legal to do home electrical work, provided it is permitted and inspected, but I'm not sure if this is true for solar as well.

Re: Zero energy ready homes are coming

#309

Post by stouset »

johnweldon wrote: post #230
masfuerte wrote: post #197

Earlier quoted context omitted.

Stop convincing them to want it

My somewhat libertarian take is that they themselves are best suited to judge what they should or shouldn't want. Not that there isn't a time for trying to bring a different perspective. But we should do it with humility, rather than assuming they're just wrong or misguided. So... yes "stop convincing them" is a valid argument. "convince them not to" is slightly shakier moral ground.

"What they should or shouldn't want" is already deeply influenced by housing policy. Cheap suburban homes which don't fully pay for their externalities are one result of this housing policy, and children grow up accustomed to this bizarro-world reality where increasingly tank-sized cars (this is—astonishingly—not even hyperbole) are the only practical means by which one can go from Point A to Point B.

Meanwhile people in Europe live in denser areas with smaller, more fuel-efficient cars or where they can do most of their commuting by foot, bike, or rail. That is the norm for people from those cultures, and so they—like us—largely choose to continue living in a world similar to that in which they grew up.

Given that one of these modes of living reliably produces a happier population and is significantly more environmentally and economically sustainable, that we're already in the business of promoting one style over another via housing policy, and that one of the core purposes of cooperative government is to find ways to promote outcomes that benefit everyone despite going against individuals' self-interest… what on earth is the problem?

Re: Zero energy ready homes are coming

#310

Post by A4ET8a8uTh0 »

bluGill wrote: post #274
Johnny555 wrote: post #243

Earlier quoted context omitted.

If you can find a way to convince Americans they don't all need a yard that can easily fit 6 (japanese) houses, we'll be well on our way. I think we are on our way there, most new developments around here have houses that are nearly the size of the lot, with a tiny back yard and smaller front yard, and little room between houses. Developers get more money by making lots small and houses big, so there’s little incenti…

Most people don't use their yard. They don't have more than a few flowers in the garden. 20 minutes with a push mower is enjoyable exercise but they wouldn't want it to take longer.

Eh. How people use their property is really their own business. I might disagree. I might despair. I might even tell them it is a bad idea, but how and whether a person uses the thing they buy is not up to your neighbor ( or non-neighbor for that matter ) to decide ( within reason, you will hear complaints about practicing on electric guitar or repairing your muscle car at midnight ). It is just a bad argument to use.

My family member just bought a ridiculous gas-guzzler to drive even more ridiculous distance to their job and still manage to muster up courage to complain about gas prices to me. It is not the use ( or lack thereof ). It is the lack basic sense.

I don't have a mega yard, because I can't afford the upkeep. If I could, I would consider it.

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