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Japan

Tokyo To Require New Homes Be Fitted With Solar Panels From 2025 (kyodonews.net) 54

The Tokyo metropolitan government has said that it will introduce a system requiring newly built homes to be fitted with solar panels from fiscal 2025 in a bid to reduce carbon emissions from the household sector. From a report: The first mandate of its kind in Japan comes as a revised ordinance on environmental security to introduce the system was passed Thursday by a majority vote on the final day of a regular Tokyo metropolitan assembly session.

According to the metropolitan government, major housing construction firms will be required to install solar panels on buildings with a total floor area of less than 2,000 square meters. Home buyers will also be required to cooperate, and those privately contracting the construction of a residence 2,000 square meters or more will be obligated to fit it with solar panels. The system will take effect in April 2025 after residents have been informed and preparations have been made with relevant businesses. The metropolitan government estimates that the 980,000 yen ($7,200) initial cost for installation of the 4-kilowatt panels can be covered within 10 years from electricity sales revenue and can be further reduced down to six years with subsidies it will provide. Subsidies for the initial costs will also be provided to leasing firms to reduce the burden on home buyers, the metropolitan government said.

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Tokyo To Require New Homes Be Fitted With Solar Panels From 2025

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  • Should be the same in all countries now especially here in the UK

    • Re: (Score:2, Insightful)

      by MacMann ( 7518492 )

      Where are all these solar PV panels going to come from? Do people understand the material and labor requirements of solar power versus other options? Because of the labor and material needed for rooftop solar the costs are nearly incredible, and mandating the installation of solar PV will create an artificial demand for more production that will drive prices higher. If every new house must have solar PV on the roof then that's just going to drive up the costs of existing homes, because if people can't af

      • Ultimately, PV panels are just special glass and the cost to make it will keep dropping. Houses are full of glass and ceramics already.
      • Where are all these solar PV panels going to come from?

        You mean for Japan? Probably Singapore.

      • by rgmoore ( 133276 ) <glandauer@charter.net> on Friday December 16, 2022 @12:59PM (#63135774) Homepage

        Do people understand the material and labor requirements of solar power versus other options?

        Given that the article includes an expected cost for the installation- as well as an estimated break-even time- they do seem to have a good handle on the material and labor cost. In practice, requiring solar panels on new construction is a sensible approach for two reasons. On the one hand, it means the solar panels will be included as part of the original building design and construction, which should reduce the cost relative to retrofitting. On the other hand, it lets people pay for their solar with their mortgage, which is usually at a better interest rate than other borrowing.

        One interesting side of this specific to Japan is that Japanese houses have a shorter lifespan than Western houses. Japanese houses are expected to be torn down and replaced every 30 years or so, meaning there just isn't as a big stock of existing houses for people to choose from.

        • Given that the article includes an expected cost for the installation- as well as an estimated break-even time- they do seem to have a good handle on the material and labor cost.

          A good test of policy is what happens once it is widely adopted. The arguments related to cost and break even are based on present day realities rather than predictable future ones.

          In the states in some of the most ideologically supportive political environments power companies are altering the deal as we have seen with recent CA NEM 3.0 approvals. The basic issue is utilities supply power, they don't act as free batteries that credit you for power when you don't need it and give you power when you do. T

          • Keep in mind, this is Japan we're talking about., and island country with extremely limited available land area. Other than rooftops, where do you expect PV panels to go? The only other viable option is agri-solar, which is potentially even more expensive since you need to build an entire tall structure to lift the panels clear of farming apparatus.

            Also, I don't know offhand what crops are dominant in Japan, and for some crops in some climates sunlight is a limiting factor on growth, making agrisolar unat

            • by jon3k ( 691256 )
              Japan has tremendous amounts of empty land [quora.com] everywhere outside of Tokyo, Osaka/Kyoto and Nagoya, basically. Just take the Shinkansen anytime and look out the window. Empty land sprinkled with a few houses for miles and miles. And given Japans expectation of continued population decline, it's not going to get any more densely populated anytime soon, maybe ever. Shoot, there are 41,000km that don't even have an owner. [economist.com]
          • by ukoda ( 537183 )
            Last things first. Designing roofs for future installs vs mandating install would be pointless. It is not like it is hard to retro fit panels etc and most builders wont bother to actually install them to keep costs down and profits up. Therefore without the actual install mandate nothing would change.

            Deploying at scale, which is what this effectively does, will effectively lead to lower system install cost from the economies of scale, so the ROI is likely to end up shorter than quoted. The real quest
        • by AmiMoJo ( 196126 )

          30 years is a bit low, generally they last a lifetime, so 50-60 years. They aren't completely worn out at that point, it's just that they depreciate with age and people strongly prefer to buy new ones. So when they get old it's usually better to tear them down and replace them with a modern home, than it is to renovate them.

          • by rgmoore ( 133276 )

            How long they last depends a lot on how well they're built and how much effort people are willing to put into upkeep. In Japan, the expectation is that houses aren't going to last that long, so they aren't built to last that long. Some of this is probably because traditional Japanese house building methods made houses that didn't last that long, and that's now a cultural expectation. Regardless of the why, though, the what is that Japanese houses are torn down and replaced much more often than Western ho

            • by AmiMoJo ( 196126 )

              The issue is earthquakes. Nothing lasts for centuries when it gets shaken like that periodically.

              When they say this temple is 1000 years old, they mean that there has been a temple here for 1000 years that gets rebuilt every now and then.

              • by rgmoore ( 133276 )

                The big issue is actually fires. Well build wooden houses are very good at resisting earthquakes, since wood has a phenomenal strength to weight ratio. There's a reason California has some of the world's oldest, tallest, and biggest trees even though it's in an earthquake-prone area; wood is incredibly good at resisting the kinds of forces encountered in an earthquake. The problem is that wood is flammable, so those wooden houses tend to burn. There's a reason Japanese cities were so devastated by the Amer

      • Forget the solar panels, how the fuck are they going to build the houses that keep the solar panels out of the dirt? Do people understand how much labor and materials are required to build a house? Where does the timber come from on a tiny island where all the forests are haunted? Where do the pipes come from when all of the metal is needed for throwing stars and Toyotas?

        I grew up in a shoe box, which we burned for heat and cooking-AND THE FIRE WAS BETTER TO WATCH THAN TV! Plus it was carbon neutral and

        • Forget the solar panels, how the fuck are they going to build the houses that keep the solar panels out of the dirt? Do people understand how much labor and materials are required to build a house? Where does the timber come from on a tiny island where all the forests are haunted? Where do the pipes come from when all of the metal is needed for throwing stars and Toyotas?

          Indeed the haunted forests have been a major obstacle for the Japanese; however, Japanese spirits can be benevolent. For example, have you met my neighbor, Totoro?

      • Solar power, even with todays inefficient panels, is enough to meet 100% of our energy demands. Reference: https://www.freeingenergy.com/... [freeingenergy.com] The biggest benefit is that it eliminates our dependency on the monopolistic OPEC mafia. You are cool with the King of Saudi Arabia waking up on the wrong side of the bed one day and demanding $150 a barrel? He's looking at how much cash you have in your wallet and charging you that whole amount .. knowing you have no choice but to pay.

        • Solar power, even with todays inefficient panels, is enough to meet 100% of our energy demands.

          This isn't in doubt. The countries entire energy demands can be met with solar alone, wind alone, nuclear alone...etc. Obviously just because something is possible doesn't make it economically or environmentally the best or even a reasonable course of action.

        • by ukoda ( 537183 )
          While I generally agree, I have 12kW of panels on my house now, there probably needs the be some qualifiers on the "enough to meet 100% of our energy demands". Once you get too far north or south the winter daylight time is a problem, so you need to route power in from closer to the equator. To get through the night you need a reasonable amount of battery storage. I have 26kWhr which works well in summer at latitude 40 south but I am yet to see how well it works in winter.

          What the Japaneses are doing
      • by mlgm ( 61962 )
        I have a very small PV for nearly 20 years now (10 panels). In that time it provided nearly 1/3 of our electricity consumption (small house) and did not need repairs. So I do believe PV is able to make a dent in our energy needs. I would expect when we would completely cover our roof we could provide our whole consumption, at least in numbers. But then you probably should have some battery storage (which we have not). The PV/battery combination certainly wouldn't provide enough power at any given time, but
      • by dwywit ( 1109409 )

        1. solar PV is 1/3 the price it was in 2009 (my last upgrade). The rollout of rooftop solar in Australia is overwhelming the grid in some places (a separate problem), so price doesn't appear to be a barrier.

        2. There's a lot of high-grade silicon in ageing PV panels. Efficient recycling can satisfy at least part of the demand

        3. Take a look at the generation statistics for South Australia. Better than 95% renewables on some days. I'd call that a dent.

        In any case, no-one with a brain cell says that solar PV is

      • Where are all these solar PV panels going to come from? Do people understand the material and labor requirements of solar power versus other options?

        Where everything comes from. The market. It's basic supply and demand. Generate demand for a product and supply ramps up. Solar panels are a produced item, not a rare exotic natural mineral.

    • by rtkluttz ( 244325 ) on Friday December 16, 2022 @01:14PM (#63135820) Homepage

      There need to be protections in place if this happens. Many solar companies have started requiring their systems solar and battery systems be connected to the internet. Enphase is a perfect example (https://support.enphase.com/s/question/0D53m00006ySLuRCAW/unimpressed-with-loss-of-local-api-connectivity-to-envoys?fromEmail=1&s1oid=00DA0000000aQ9D&s1nid=0DB2G000000Kz2X&s1uid=0053m00000CfQbs&s1ext=0&emkind=chatterCommentNotification&emtm=1671020160542). They are trying to change their equipment to require internet connectivity and threatening people with voided warranties if you do not. This is ludicrous from a security standpoint. Homeowners should be allowed the same security as commercial systems. No company on the planet exposes control systems to the internet. Not even accounting for the fact that it is stupid as hell that you have to connect to the internet, authenticate to someone elses servers and ask permission from it to get access to your own data or change settings or modes on equipment that exists behind your firewall. Cloud requirements should never be more than an opt in feature for those that want it. For something like this to be forced on homeowners, there needs to be additional protections that ensure that you still have the ability to run isolated control networks for your things that only get connected to the internet when there is a documented need, otherwise the home network is an island.

      • by ukoda ( 537183 )
        If I had mod points I would mod the parent post up as "Interesting". I have been working on retrofitting home automation to a 1970's house I recently brought. I want everything to run 100% locally. My Tesla gear is the biggest pain, for the reasons you point out. For the PowerWall I can get data from the gateway locally, which is nice, but I have zero local control over what it is doing. Controlling the charging of my Tesla car is a hassle. I can adjust the the car's charge current dynamically to trac
      • by AmiMoJo ( 196126 )

        That's why I recommend using a separate network for devices like this. A network with no internet access, so they can't remotely update it, and it is much harder to hack.

        That way they can't take away functionality after they sold it.

    • by shanen ( 462549 )

      Should be the same in all countries now especially here in the UK

      Not a particularly deep or insightful FP, but it doesn't deserve so much negative moderation. Ergo the quoting of the content.

      I did watch the story on NHK World via the Internet. I think your premise is interesting, but many, probably most, countries don't have the resources to afford it. That's mostly financial resources but it also involves some of the necessary infrastructure. If you focus it on high-end housing, then your suggestion would make pretty good sense, and there's even an economic argument tha

    • It's a great idea but it'd vary according to climate. In Japan, the best option may well be PV panels. In contrast, they passed a law in Spain whereby all new houses have to come with solar water heaters. They're cheap, low-tech, simple, durable, & use zero energy. Because Spain is warm & sunny, it's basically free hot water all year round. Other climates & geologies will have other opportunities. It makes sense for govts to investigate, explore & encourage sensible energy saving & produ
  • Need to go further (Score:1, Interesting)

    by backslashdot ( 95548 )

    Property taxes should be higher if you do not have solar. This frigging oil and centralized dependency is a national security issue and causing a lot of trouble. No need to fatten up middle eastern sheikhs, we do not want them to get diabetes from being obese. They earned enough from zero intellect, they can do other things now.

    • ...we do not want them to get diabetes from being obese.

      Of course we do.

      "You have the right to think before you type... "

    • "Property taxes should be higher if you do not have solar. This frigging oil and centralized dependency is a national security issue and causing a lot of trouble. No need to fatten up middle eastern sheikhs, we do not want them to get diabetes from being obese. They earned enough from zero intellect, they can do other things now."
      was hardly a troll so one wonders who was offended and why.

      Oil has been a national security issue since WWII. That's why the US spent trillions in treasure and thousands of lives d

      • "Property taxes should be higher if you do not have solar. This frigging oil and centralized dependency is a national security issue and causing a lot of trouble. No need to fatten up middle eastern sheikhs, we do not want them to get diabetes from being obese. They earned enough from zero intellect, they can do other things now."
        was hardly a troll so one wonders who was offended and why.

        Oil has been a national security issue since WWII. That's why the US spent trillions in treasure and thousands of lives due to global market dependence on our thoroughly unsavory Gulf frenemies. Oil is behind Operation Ajax which backfired when the incompetent Shah ran away leaving Iran to the mullocracy his tyrannical policies made popular.

        It was modded "troll" because he was trolling, same as you

    • Well they sort of are. From the article, "The metropolitan government estimates that the 980,000 yen ($7,200) initial cost for installation of the 4-kilowatt panels can be covered within 10 years from electricity sales revenue and can be further reduced down to six years with subsidies it will provide." Where do you think those subsidies come from usually? Prop tax maybe? So everyone pays prop tax but those who get panels will get a rebate from the incentive. I just hope they don't do what california just d
    • > Property taxes should be higher if you do not have solar.

      Difficulty: Such a policy would be extremely regressive, punishing property owners who maybe already have trouble paying their taxes, let alone able to afford capital investments, with even more taxes.

      You need to make having solar less expensive, not not having solar more expensive. There's a mechanism to do that already that's been proven to work pretty well: Feed-in tariffs.

      Bonus points if you include higher FIT rates if the energy is delivered

  • by WaffleMonster ( 969671 ) on Friday December 16, 2022 @12:58PM (#63135770)

    "in a bid to reduce carbon emissions from the household sector"
    "bid to reduce carbon emissions from the household sector"

    If the goal is reducing carbon emissions perusing nuclear or wind are better policies with far higher returns, lower monetary and environmental cost. They are safer to operate and maintain than residential rooftop.

    Residential rooftop is 2x the cost of a PV farm and has inherent weaknesses from shading due to obstructions, inability to benefit from bifacial production, higher ongoing maintenance costs. Roofing costs far more to replace or repair when solar is present. Solar panels deny roof access to firefighters and represent additional fall and fire risks during installation, maintenance and use.

    The better policy is to use the money to fund wind energy projects instead of rooftop solar. Japan has infinite offshore potential.

    • by necro81 ( 917438 )

      Residential rooftop is 2x the cost of a PV farm and has inherent weaknesses from shading due to obstructions, inability to benefit from bifacial production, higher ongoing maintenance costs. Roofing costs far more to replace or repair when solar is present.

      For a country with very little available land, putting PV on top of existing structures makes perfect sense. The yield may not be as great as having those same panels out in an open field - but if you can't get an open field in the first place, then p

    • by ukoda ( 537183 )
      I don't think any of your points are wrong but I still think what they are doing in Japan is a good idea. It will help get their grid cleaner quicker if done in parallel with larger commercial solutions. Also having distributed power generation helps with grid costs and reliability.

      Your 2x the cost point may be valid if you simply look at the total system cost of power generation but if you look at it as an individual that 2x cost doesn't apply, it the ROI period that counts.
    • If the goal is reducing carbon emissions perusing nuclear or wind are better policies with far higher returns

      Reduce emissions when? No really. Let's run two numbers:
      This policy: In 2025 houses will be reduced requiring significantly less total primary energy and all offsets are green.
      Your policy: In 2025 nothing will have happened. In 2030 CO2 emissions will be significantly higher, both through the less efficient housing requiring more power drawn from the grid (this will require expansions in power plants, and since we haven't built nuclear yet, you don't like solar, and they have no space for wind you can bet y

      • This policy: In 2025 houses will be reduced requiring significantly less total primary energy and all offsets are green.

        Your policy: In 2025 nothing will have happened. In 2030 CO2 emissions will be significantly higher, both through the less efficient housing requiring more power drawn from the grid (this will require expansions in power plants, and since we haven't built nuclear yet,

        My recommendation is instead of investing whatever money would have been spent on rooftop PV to instead use that money for wind projects that provide more energy more of the time for the same input cost and do so with LESS CO2 emissions.

        you don't like solar,

        Personally I love solar and I think it has a bright future where it is deployed properly with reasonable mix of energy sources. What I don't particularly care for is piecemeal rooftop solar because it is an unnecessary risk and costs more than better renewable alternatives.

    • by AmiMoJo ( 196126 )

      Nuclear isn't going to expand much in Japan. There are few places to build it, and operators are not keen on that kind of risk after what happened to TEPCO (the owners of Fukushima).

      Japan has excellent wind resources, and solar coincides with demand in the summer. There is also the need to change electric vehicles. Solar PV will be supported by products like washing machines with timers.

      Japan is already good at this stuff because it became necessary when Fukushima resulted in all nuclear power being offline

    • by mjwx ( 966435 )

      "in a bid to reduce carbon emissions from the household sector"
      "bid to reduce carbon emissions from the household sector"

      If the goal is reducing carbon emissions perusing nuclear or wind are better policies with far higher returns, lower monetary and environmental cost. They are safer to operate and maintain than residential rooftop.

      Japan is a very shaky place, making nuclear power quite difficult.

      Offshore wind is an option, but realistically they need all 3 working together, solar, wind and nuclear.

      The major issue with this policy is how much of Tokyo is going to be built new? The real problem is that it's a drop in the bucket compared to Tokyo's energy needs.

  • For a country known for cramped living conditions, I don't think that 21,500 square foot houses are at all common.

    • From the article, "buildings with a total floor area of less than 2,000 square meters." with the operative words being less than. So pretty much all residential and small commercial. Sort of surprised they did not just say all.
      • Read the sentence after that one..
        "Home buyers will also be required to cooperate, and those privately contracting the construction of a residence 2,000 square meters or more will be obligated to fit it with solar panels."

  • I remember talking to someone from Japan twenty or so years ago.

    I was surprised when he told me Japanese homes have very little in the way of insulation, making them cold in the winter, hot in the summer, and energy inefficient.

    Has that changed? Are new homes in Japan properly insulated?
    • That would depend I guess on the type of home. A traditional home as you have seen in movies made with wood and paper covered walls probably has little insulation. In an urban setting like Tokyo, the buildings are probably constructed with more modern materials and construction techniques that replaces wood with concrete for the outside walls.
  • Note that this mandate only applies to Tokyo-to which makes up about one third of the Tokyo metropolitan area.

  • I have been saying this all along. However, for most nations, they are doing it wrong.

    Require that all new buildings less than say 5 stories to have enough on-site UNSUBSIDIZED AE to equal or exceed the HVAC's and hot water's BTUs.

    This simple requirement would get new buildings to insulate far better, skip using fossil fueled furnace and move to Heat pumps. Ideally, these would be geothermal based so that the BTUs would be extremely low. So basically, it uses the high price of AE as incentives for builders to do the right things.

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