Photon to electron to chemistry to electron definitely has a huge efficiency advantage over photon to electron to photon to electron. The battery has about >90% round-trip efficiency while the wireless power transmission over thousands of miles has on the order of 33% round-trip efficiency once you add everything up. That means that in order to get the same energy, you need almost as big of a solar array as you would in a good desert location even though you get 24/7 sunlight!
And it's not even the conversion efficiency that's the problem. It's the cost of the conversion equipment. The power electronics, the microwave amplifier, the array, the receiver array, rectifiers, and power electronics as well as transmission all has a MUCH higher cost than the actual solar cells. Additionally, the minimum size space based solar power satellite and receiver station is super expensive, and the situation only starts looking like it might be worth it when you approach multiple Gigawatts per installation.
In some ways, space based solar power is based on the idea that solar cells are expensive and scarce and their output should be maximized. Nowadays, that's a strange thing to believe because solar cells go for 16 cents per Watt on the spot market, so we tend to emphasize the constancy. But really, even that is falling prey to technological advances in battery technology.
As far as "ground stations are a small portion of the total cost" and "point power to the places you need it most," that's simply not true. The ground stations would rival an equivalent solar array in cost, not even counting the space-based portion at all! But I suppose the in-space portion WILL be crazily expensive, so you might still have the ground-stations a "small portion of the total cost" while still being crazy expensive.
And due to the diffraction limit and required safety margins, your ground stations will have to be huge. You're not just going to beam power into the middle of cities with high aircraft traffic and safety concerns. The exception to this would be if you used much shorter wavelengths, such as mm waves or lasers, but there the cost of everything (amplifiers, optics, etc) is much greater, the realistic round-trip efficiency drops to like 10-20%, and you become much more susceptible to weather. Oh, and what you're building now looks a HECK of a lot like a weapon.
Well all I can say is check my source, which covers all of this, with extensive references on efficiency, cost, and lots of other practical concerns. Some of the key research was done by NASA in the past decade.
The cost of a 2GW ground station is $700M, which is pretty decent for a peaking plant that doesn't require fuel.
The idea isn't so much that you have to minimize solar panel size, as that you can entirely eliminate the need for storage, which is a big deal once we try to get past fossil backup. To see the scale of that problem, read A Nation-Sized Battery, by Berkeley physics prof Tom Murphy. Even if he's too pessimistic by a factor of ten, storage looks like a daunting problem.
Yeah, I've read that blog many times. The author wastes his intelligence by refusing to pursue creative solutions to problems vs just trying to find ways to make the problem unsolvable.
The answer to season storage for solar, for instance, is to make the solar array larger, not to have a nation-sized battery. That means you only need a day or so of battery, not a week or months.
Also, why would you want to eliminate storage? Just like nuclear power, you'd want to use storage at very least to help convert a constant baseload power source into one that can follow day vs night demand. That is ultimately cheaper. And his complaint that batteries might require service? Well first of all he's off by at least an order of magnitude in cycle life, and second of all, yeah, why wouldn't we do a lot of service on batteries like we do on the rest of our energy infrastructure? That's a weird thing to focus on.
As far as material shortages: I find this highly doubtful. Lithium is not fundamentally rare. "Proven reserves" might be, but that is almost entirely a function of demand (provided your mineral isn't fundamentally rare, which lithium isn't). Other metals used in batteries, like cobalt, can be substituted by other more abundant minerals if desired, especially in grid storage. (LiFePO4 is one such chemistry.) That the author of that blog seems to not realize this pretty obvious fact strikes me as naivete dressed as "skepticism."
And it's not even the conversion efficiency that's the problem. It's the cost of the conversion equipment. The power electronics, the microwave amplifier, the array, the receiver array, rectifiers, and power electronics as well as transmission all has a MUCH higher cost than the actual solar cells. Additionally, the minimum size space based solar power satellite and receiver station is super expensive, and the situation only starts looking like it might be worth it when you approach multiple Gigawatts per installation.
In some ways, space based solar power is based on the idea that solar cells are expensive and scarce and their output should be maximized. Nowadays, that's a strange thing to believe because solar cells go for 16 cents per Watt on the spot market, so we tend to emphasize the constancy. But really, even that is falling prey to technological advances in battery technology.
As far as "ground stations are a small portion of the total cost" and "point power to the places you need it most," that's simply not true. The ground stations would rival an equivalent solar array in cost, not even counting the space-based portion at all! But I suppose the in-space portion WILL be crazily expensive, so you might still have the ground-stations a "small portion of the total cost" while still being crazy expensive.
And due to the diffraction limit and required safety margins, your ground stations will have to be huge. You're not just going to beam power into the middle of cities with high aircraft traffic and safety concerns. The exception to this would be if you used much shorter wavelengths, such as mm waves or lasers, but there the cost of everything (amplifiers, optics, etc) is much greater, the realistic round-trip efficiency drops to like 10-20%, and you become much more susceptible to weather. Oh, and what you're building now looks a HECK of a lot like a weapon.