Doesn't it make far more sense to just put solar panels in a field like this, instead of doing custom work putting them on top of individual homes which may have shade or directionality issues? Even disregarding the agriculture happening, why don't we do this more often?
At least in the Netherlands, you don't pay energy taxes on electricity generated "behind the meter", ie from solar panels on your own house. Electricity that comes from the grid, no matter how it is generated, comes with grid fees and energy tax. Seeing how the price for bulk electricity is currently ~0.09 EUR/KWh and the taxes+ grid charges come to ~0.15 EUR/KWh for a total price of 0.24 EUR/KWh, electricity from solar panels on your own house instantly becomes about 3x cheaper than if you put the same panels elsewhere in a field. Thus, many people opt to put the panels on their home since the installation cost is not that high and the financial benefits are substantial.
Personally the addition of solar panels to my roof has the added appeal of reducing the wear and tear of my roof.
The panels must be in the sun, so they'll always be getting that UV damage if they exist outside at all. May as well let them do double duty on my roof in that role.
It'll also help keep the solar thermal gain out of the house, reducing cooling costs...
Disregarding taxes and financial incentives that may bias things, putting it in a field means you don't need to work on a roof to maintain it, you aren't limited by roof area, and you don't need to worry about the roof weight limit or damage during installation.
I think there is no question a field is preferable if there are fields to work with. Of course, in a city that isn't much of an option and there are significant advantages to point of use generation (i.e. no need to upgrade power lines from rural solar fields to a city center).
I used to live in Boulder, and while I'm not sure exactly which field they're talking about it was not a long bike ride into farmland. I can imagine it working much better there than a bigger city.
I don't know about "more often" but we certainly do it pretty normally. There are entire businesses built around obtaining rights to use land, building solar farms, and selling the tax credits.
Panels on my roof reduce my electricity costs. Put in a field by someone else does not. My panels are not visible from the street and will have paid for themselves within a few years, so there isn't really a reason not to. I think 30-40% of homes in my city have panels on their roof.
This ignores any feed-in tariff which is declining, though there were early adopters with a locked-in rate who wouldn't have paid for electricity for years now.
I think the simplest answer is that we put panels wherever it's easiest. With no existing infrastructure in a random field it takes more effort to get the panels to function, compared to mounting on a roof and wiring in to an existing grid. The upfront cost has always been a barrier to entry, so higher costs turn the average consumer away.
But you can install a whole lot of panels in a field, which has a significant amount of labor price advantage. Running a cable over might not be too bad.
From what I understand even at 100 miles the loss of energy is about 5 percent. You may need to build more transmission lines at some point - but I would still wager there is no way that it is energy efficient to build a frame upwards + have people get on special tools to maintain things 10 feet above the ground.
In places like Colorado there is very cheap land that is not very good for farming about an hour away from Denver and it certainly seems like it would be cost + energy efficient to build out there instead of up.
I'm not arguing for a giant solar array in the Sahara, just using marginal farmland that surrounds many cities to put solar panels instead of scattered about on roofs in the city. And with most solar installations it just dumps electricity back into the grid so I'd think losses would be similar.
>Doesn't it make far more sense to just put solar panels in a field like this, instead of doing custom work putting them on top of individual homes which may have shade or directionality issues?
Depends on what you're optimizing for. If you're considering solar purely from the angle of replacing carbon-thermal generation on the grid then sure, large arrays are more efficient, offering more room for amortization of fixed costs, more optimization for solar gain, and more room for optimal hybrid usage like this example.
However, buildings need roofs anyway, and will in turn get sun exposure. Since solar tech like tiles can take the place of traditional roofing, there are some double gains to be had there in that they're both doing the job of protection from the elements and taking otherwise mostly wasted energy and doing some work with it. Depending on how one gets into the weeds on aesthetics (like if they wanted nicer tiling anyway) the marginal extra capex of tiling may well be worth it as costs come down further. Building-solar also can help provide resiliency to grid damage, which by definition grid feeding cannot. For people in areas where they'd otherwise be running generators anyway, solar/res-wind+battery (and as BEVs take over near everyone will have an extremely sizable slab or three of battery around much of the time) can be compelling. Still more upfront, but maintenance-free for a decade or more and constantly providing some ROI (and effectively constant verification everything is working), whereas hydrocarbon generators require regular maintenance/testing which cost money and generate zero return otherwise, they just depreciate. And local solar/wind/utility resources are going to affect the time horizons for all this.
So basically there are a ton of new variables and enormously more scalability up and down the spectrum for renewables and batteries. Doing the math is in turn going to be very individual, but it will often still make sense to do both.
Also:
>why don't we do this more often?
I mean, we're still in a pretty steep part of an S-curve here. It's just plain early days. People are still experimenting with stuff like this and learning what works. Unit costs are dropping, which in turn changes what projects make sense which in turn changes demand and thus unit costs. Grids are adapting and getting smarter. Both storage and opportunistic demand are doing the same in parallel in a variety of ways. Stories like this where someone tries some new stuff and it works out well will make others perk up and take notice. There will also be things tried that don't work out. Going to be a wild decade.
Unfortunately second-order effects make rooftop solar less desirable than you'd think. In urban areas built to adequate densities (> 100 residents per acre) there's not enough roof area to power those residences, so you need the off-site generating resources anyway. Denser development has significant demand efficiency payback, but it always reduces the ratio of on-site solar generating resources per capita.
On the other hand you also have the phenomenon that after a person puts solar power on top of their little detached single-family house they start yammering about "solar access rights" to stop the construction of even slightly taller buildings nearby. Boulder, Colorado is ground zero for this kind of stupidity, see their "solar access protection" law which is as naked an act of NIMBY greenwashing as anyone has ever seen.
I don't think anyone who actually bothers to run the numbers suggests that solar will meet 100% of a buildings energy needs.
However, even at 100 residents per acre[0], it's utterly possible to put about 4-6kw of panels and a solar water heater on every house. Having both of those on a duplex, I can tell you that my power bill is basically nothing now.
Naturally, that power output will differ by location, but it's doable.
[0] Based on my local area, this is a mix of row-houses, semi-detached, and fully detached housing.
