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Earth Power

Renewable Energy Could Use 50% Less Land, Study Suggests (washingtonpost.com) 63

The Washington Post looks at a new study co-authored by Nels Johnson, senior practice adviser for renewable energy development at the Nature Conservancy nonprofit.

Its underlying point: the current way of building renewables will not work. "If we take the business-as-usual approach, land conflicts will probably prevent us from getting to these ambitious clean energy targets," said Jason Albritton, director of the Nature Conservancy's North American climate mitigation program and one of Johnson's co-authors... In its report, the Nature Conservancy describes two different futures in which the United States achieves net-zero carbon emissions by 2050. In one future — call it "business as usual" — wind and solar farms are built haphazardly, with little consideration for land impacts. In the other future, developers use land more efficiently. Business as usual would require 266,410 square miles — an area around the size of Texas — to fit all the solar panels and wind turbines, plus batteries to store electricity when sunlight and wind are unavailable and long-distance transmission lines to bring power from rural areas to towns and cities.

The researchers used a statistical model to discover the suite of technologies that would minimize land impacts. A smarter strategy, they found, could slash that footprint by more than half, to 114,642 square miles — a little bigger than Arizona. That's still a lot of land, but it would reduce the opportunities for conflict, the researchers said. The model recommends building more solar and less wind, since photovoltaics produce more power with less land than turbines do... The study sees rooftop solar generating far less power than large solar farms. If one in three rooftops have solar panels by 2050 — a high-end assumption — rooftop solar would contribute 15 percent of U.S. solar power, according to the researchers. "It's an important part of the picture, but it will not ever be totally sufficient," Johnson said.

The researchers also found land savings by avoiding productive farmland and instead building on abandoned fields or rehabilitated mines, landfills and hazardous waste sites known as brownfields.

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Renewable Energy Could Use 50% Less Land, Study Suggests

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  • by ffkom ( 3519199 ) on Saturday June 03, 2023 @05:10PM (#63573957)
    Given how much fine farm land, which could be used to grow food, is currently already used to grow energy plants for bio fuels, I am surprised how they are now concerned about PV occupying too much space. There are so many places where PV can be installed without disturbing anything/anyone, and where no other usages suffer... likewise with wind farms, especially in a country that has so many not densely populated areas... plus lots of coast line for off-shore wind farms.
    • In the US biofuel is almost synonymous with ethanol [eia.gov]. Nobody on either side likes ethanol except farmers and their representatives. About 45% of US corn is for ethanol [usda.gov], so corn farmers are almost as threatened by the EV conversion as Saudi Arabia... I suppose they're taking legislative measures to enforce its continued production and consumption as we speak.
      • Until cellulosic biofuel processes are efficient, scalable and cheap it will continue to be a niche thing.

        Corn takes too much input materials, water, fertilizer and such to be worth the process. The ability to feed a process the garbage plants like kudzu is required for it to be a serious source of energy an even now it's been so long that biofuels for passenger vehicles is a nonstarter.

        It will still have important uses in commercial and industrial sectors though.

    • by flyingfsck ( 986395 ) on Sunday June 04, 2023 @01:54AM (#63574659)
      From what I saw, wind turbines have very little impact on farming under it. There are hundreds of turbines close to where I live and life goes on as before.
    • Corn for ethanol is about 35M acres, or 55K sq mi. Or about half what the new projected need is.

      I suspect as well that they allowed too much land for wind, which lives with ag very nicely.

    • Plus, if you build vertical solar power installations you use way less land and get a bit of shade in return.
    • which could be used to grow food

      Are you hungry? No that's a legitimate questions. Before you discuss what we "could" be doing with any land the question we need to ask is what resource do we actually require.

      The USA is the world's biggest exporter of food.
      The USA is the most obese nation in the west.
      The USA has energy production feedstock (corn) as it's single largest crop.

      Those three statistics together highlight that you don't really need to concern yourself with using farmland for more food.

  • Called a desert. Yes transmission losses and infrastructure needed for that, but wouldn't all that just mean a bit more land needed in the wide open unused desert? Desert is fine as it seems to work for building civilizations in Arizona and California just fine.











    /s

    -Time to get dessert.
    • Desert, sure, but a few rattle snakes may be inconvenienced.
    • There are many solar plants in the desert and there are some downsides to having them all so closely packed in including killing many species that live underground in the desert. I do not know enough about solar panel placement to comment on the conclusions within the article. However, in *some* cases, things that are well planned come out better than things that are put together haphazardly. See "The Cathedral and the Bazaar" (very relevant on /.) for good examples. A Cathedral takes careful planning.
    • They're talking about reducing projected land use from 7% to 3.5%. I've no idea if that solves any real problems or not.
    • Sand is extremely abrasive, A windy day in a desert is like a natural sandblaster, combined with the extreme swings of temperate (deserts loose heat at night) which will further stress materials, you are looking at a lot of added cost and limited lifespan.
  • Seems based on the premise that land used for renewable power production can't also be used for other things. Seems a dubious assumption.
    • by XXongo ( 3986865 ) on Saturday June 03, 2023 @05:20PM (#63574007) Homepage
      Actually, turns out that using the land for other purposes as well is mentioned. Whoever wrote the summary, however, just decided not to mention it.

      From the executive summary of the report [nature.org] cited:

      Researchers considered three such approaches in this study, all of which are effective ways to reduce environmental and social impacts where they can be deployed: 1) the co-location of wind and solar; 2) agrivoltaics (siting fixed photovoltaics (PV) panels on agricultural land); and 3) fixed tilt PV (see Box 4). The opportunity for co-location is most prominent in the southern Great Plains. Development of agrivoltaics is well-suited to vegetable and fruit growing areas in various parts of the country. Currently, the use of agrivoltaics is an uncommon practice that is gaining traction and is likely to grow as innovations advance and incentives offset additional costs.

      And the WP article [washingtonpost.com] linked also mentions it.

      In places where fruits and vegetables are grown, such as eastern Washington, the central valley of California, and parts of Colorado, solar panels and agriculture could share space rather than compete for it. At 24-acre Jack’s Solar Garden in Boulder, Colo., 3,200 solar panels share space with tomatoes, potatoes, garlic, lettuce and more — although squash has languished under the photovoltaics. The experiment generates enough electricity to power 300 homes, according to the farm’s website, but could provide a model for larger projects.

      Farm owner Byron Kominek sees promise in growing crops among solar panels, but “the holy grail,” he told me, is agrivoltaics on cattle ranches. The cows cherish the shade, but the trick is to have good forage under the panels so the cows stay busy eating. “If you have beat up land,” Kominek said, “they’re gonna be bored and screw with your solar array.”

      • by ffkom ( 3519199 )

        The cows cherish the shade, but the trick is to have good forage under the panels so the cows stay busy eating. “If you have beat up land,” Kominek said, “they’re gonna be bored and screw with your solar array.”

        I've heard that cows don't like touching electric fences. Given the already required wiring for PV, it should be easy to wire the posts on which the panels are mounted such that cows will avoid touching them...

        • No one like touching electric fences, that is why they work. The posts can't be grounded is the problem, so you need an insulating block between the bottom of the post and the foundation. It's a solvable problem.

          Since you do not want to electrocute the cows with full grid power you will use the same fencers everyone else uses. High voltage low current.

          https://www.tractorsupply.com/... [tractorsupply.com]

          • I so wish I had mod points to give you.
          • Trying to insulate the post from the ground is madness. It makes far more sense to wrap an insulator around the post, and then wrap a wire around the insulator. This is how electric fences actually work, the wire is separated from the post with an insulator.

            • That might cost more than a block of plastic between the post and the foundation. The usual way is a whole lot of little fences, one around every pole. Having had to walk the fence to find the ground in my youth I'm trying to minimize that.

  • They'll be like, "Wait, you though it made sense to just burn stuff? WHY would you think that???"
  • by Anonymous Coward

    How many sq miles of parking lots are there?

  • In one future â" call it "business as usual" â" wind and solar farms are built haphazardly, with little consideration for land impacts. In the other future, developers use land more efficiently.

    They should try using more realistic economic modeling and see what sort of scenario that comes up with.

    The real "business as usual" involves human values mapped into prices amd a lot of smart (but selfish) people thinking about what to do that would increase value - at least the part in their pockets. Tha

    • The free market solution would definitely be tragedy of the commons. (I'm tempted to say "was" instead of "would be"...)

      The real heart of the problem, not answered rationally by science or economics, is whether/how much we should care about what will happen after we are dead. Arguably the "smart but selfish" answer is "not at all." But then humanity is not sustainable.

  • The idea of putting solar panels between tracks is a great one. Using an automated layer is so brilliant.
    But, the best places to put these are on buildings, esp with dark tops, as well as over asphalt parking lots.
    putting these on at fields, deserts, etc are horrible ideas. And utility PV makes little sense.
  • For any sort of US-centric analysis, I tend to ignore it if they don't start by reminding their readers that the US has three grids with minimal power transfers between them. Renewable-only solutions for the Western Interconnect are straightforward, if not simple. Lots of marginal land with rich renewable resources within reasonable distance of the handful of major demand centers and only a couple of realistic layouts for the necessary bulk transmission network. The Eastern and Texas Interconnects are a
    • Re: (Score:2, Troll)

      by MacMann ( 7518492 )

      For any sort of US-centric analysis, I tend to ignore it if they don't start by reminding their readers that the US has three grids with minimal power transfers between them. Renewable-only solutions for the Western Interconnect are straightforward, if not simple. Lots of marginal land with rich renewable resources within reasonable distance of the handful of major demand centers and only a couple of realistic layouts for the necessary bulk transmission network. The Eastern and Texas Interconnects are a different story.

      For any US-centered analysis on renewable energy there needs to be a reminder that the USA is quite unique in the size of the nation, the diversity of climate, the small number of people per area, size of the economy, and perhaps other differences depending on wherever else someone might try to apply such an analysis.

      Take this same analysis to someplace like South Korea, Japan, or UK and it should become immediately apparent that there's not the same kind of wide open unoccupied spaces for collecting wind a

  • The area calculations included no area for mining of materials. That's not being quite fair when wind and solar require so much more raw material for the same energy or power as compared to coal, natural gas, or nuclear fission. Here's a few articles from a quick internet search that explains the concern:

    https://blog.ucsusa.org/charli... [ucsusa.org]
    https://www.igfmining.org/mine... [igfmining.org]
    https://www.popularmechanics.c... [popularmechanics.com]

    These don't look like people that are the biggest advocates of fossil fuels or nuclear fission, quite the

  • by SoftwareArtist ( 1472499 ) on Saturday June 03, 2023 @09:53PM (#63574441)

    We could easily put much more solar on roofs, if we just chose to do it.

    When I put solar on my house, I learned you aren't allowed to install more than you plan to use. You have to justify the amount of capacity you're installing, providing electrical bills for the last two years and listing any new uses you plan to add in the near future, like buying an electric car or getting a heat pump. I could easily have fit twice as many panels on my roof, but I wouldn't have been allowed to.

    Not that I wanted to. Our economic model is that the homeowner pays upfront to get solar and doesn't get paid much back if they produce more than they use. In that model, most people wouldn't want to fill their roof with panels that produce more energy than they need. But if the goal is to serve the whole community by finding places to install solar, we're wasting tons of space on rooftops.

    • You'd have to have a massive roof for solar panels to provide for all your needs 24/7 with a battery backup system.

      • You'd have to have a massive roof for solar panels to provide for all your needs 24/7 with a battery backup system.

        For the grins and giggles I did the math once on if it were possible to meet my energy needs through the year if I covered my roof with solar PV panels. What I discovered was interesting.

        I live in the Midwest USA so I was using numbers I found on the internet that gave some averages on electricity consumption and sunlight through the year. I found that in the summer I'd likely meet all my electrical needs for air conditioning, lighting, cooking, and so on with some extra left over to charge an EV. In the

        • If there's a large number of people in a neighborhood with these massive solar panel arrays on their rooftops then that could create grid stability issues.

          Solar panels don't cause instability, they simply don't contribute to stability. Large, spinning masses contribute to stability. The problem comes when the large, spinning masses (generators) are disconnected when other things are providing energy. Synchronous condensors can also do that job, but some will need to be installed if there's too much energy

        • by AmiMoJo ( 196126 )

          You forgot to post your numbers so we can critique them.

          Most likely your problem is that your house is badly insulated so needs an incredible amount of heating and cooling. Your sock puppet posted about spending $180,000 on solar last week, and in that case their house was using something like 4x as much as the average northern European, and 20x as much as a properly insulated home.

          For reference, the Passivhaus standard is a maximum of 4.5kWh/day on HVAC. I guess you also do a few thousand kilometres a day

      • Most houses can do with 12 panels.
      • The limit is based on total use over a year. We have net metering. We reached the limit covering only about half the roof with panels. It produced more than we used during the summer and less in the winter.

    • We could easily put much more solar on roofs, if we just chose to do it.

      Well, yes, the act of putting solar panels on rooftops is trivial enough but there's plenty of issues to consider. Where all these solar PV panels will come from is a big issue. There has to be the raw materials mined, and factories built, to produce enough solar panels to cover more rooftop area with solar panels. This is on top of the added labor, and therefore added cost, of putting PV panels on rooftops over utility scale solar where the panels are about waist high. Working on a slanted roof is goin

      • You're giving all the reasons a limit makes sense within our current economic model. But that isn't what the article was about. It was about the huge amount of land used to generate renewable energy, and ways to reduce it. It said rooftop solar could never contribute more than about 15% of our energy needs. That's what I was responding to. My point was that it could easily contribute much more if we switched to a different economic model.

        Suppose we had a model where people could say, "Hey power company

    • We could easily put much more solar on roofs, if we just chose to do it.

      That's not as easy as you think. Countries which are ahead of the USA in terms of rooftop solar are finding out that there are very real limits unless there is huge infrastructure investment. Some countries are in parallel offering huge subsidies that make solar incredibly attractive while at the same time rejecting solar applications due to grid capacity.

      Money isn't even the issue here, a modern solar panel can easily pay for itself in a few years based on just offsetting midday use without considering fee

  • "Shifting away from wind and toward more solar development reduces impacts to both general
    croplands and highly productive croplands. "

    They don't like windmills because birds and instead want to push agrivoltaics instead which nobody is interested in. Wind can be colocated on cropland with ease and is far less polluting and more productive than PV.

  • They could put solar panels over every uncovered parking lot and on every major commercial building if everyone was willing to cooperate on actually doing it right. The land usage would practically be negative then, because you're adding secondary value; shade for the parking lots and reduced air conditioning bills for the office buildings. In this way, instead of having to find unused land you're actually reclaiming already used land without preventing the original use. And yes, there's more than enough of

  • Business as usual would require 266,410 square miles â" an area around the size of Texas â" to fit all the solar panels and wind turbines

    Hear me out... let's just use Texas. They need grid connections anyway.

  • Why does most reporting claim decades will be needed for token results. Solar panels on roofs are already seeing significant uptake and with the price of panels continuing to fall the question is more "why not?". The ROI of roof top solar panels is already pretty short and it is only going to get shorter, making the choice a simple one. Put them up there and forget about them. I would expect the 33% figure to be reached in 5 to 10 years and by 2050 it is likely to be more like 80+%.

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