Japan proposes orbital solar farm by 2020.

[Streetwind]

http://www.dailytech.com/Fukushima+Legacy+Pt+I+Japan+Plans+Mankinds+First+Solar+Farm/article34854.htm

TL;DR - giant solar cell array with integrated microwave transmitters, gravity gradient stabilization, ground station to receive and convert to AC power. Demonstration launches by 2018, commercial test operation by 2020, up to 1 GW of output by 2040.

It's just a proposal at the moment, but the government is apparently taking it into serious consideration.

Can they pull something like that off, and be cost effective - or would they be begging for a high-profile failure?

[Tommygun]

It's just too expensive, look at what the ISS cost to build.

They would be better off building wind farms off the coast.

[Seret]

Presumably they're looking for something to replace nuclear for base load generation. I remain unconvinced that SPSs can provide base load economically. Base load is a fixed contract, but the price per MWh is rock bottom. PV isn't economical for base load at ground level, and going to orbit only improves insolation by a bit over 30% per unit area, and a bit over double in terms of time. You just aren't going to get enough of a performance increase to make lifting all that mass into orbit economical. The cost of the receiver would be considerable too, due to the amount of area it would take up.

[Nibb31]

I don't see it becoming a high-profile failure because it most likely won't go beyond the trade study phase, which is why a lot of money is spent on trade studies in the first place: to weed out bad ideas.

Not only is it uneconomical by costing more energy than it will even produce, but the whole idea of high energy microwave transmission is unproven and could potentially have some nasty side effects.

[KerbMav]

And if the goal is not to find a cheaper way to generate power, but to use an alternative renewable energy source and they are just going orbital to better bridge the night? If we do not only compare penny with penny but also pros and cons in general?

But: Is it safe to beam back high loads of energy via microwaves into our atmosphere?

[StuntMax]

...reminds me the good old days of SimCity 2000, when you could launch a similar contraption to power your city.

Seemed really sweet, untill the MW beam randomly started hitting something different than the receiving station, like an hospital or that old fission reactor waiting to be dismantled

I'm on the "too expensive for extended use in the next 10 years" boat, but IMO any realistic proposal leading to riddance of fossil fuels is worth being investigated and tested.

[Streetwind]

But: Is it safe to beam back high loads of energy via microwaves into our atmosphere?

The article says that the amount of microwave radiation directly on the receiver would not even suffice to heat a coffee cup. Facility workers can make do with basic protective gear, and the radiation drops below regulation levels at 2km from the receiver (which will be built offshore).

[andrewas]

Remember, the beam from these things is massive. To do it right, you need a rectenna ten km on a side, meaning you can power an entire country with a fairly low energy density. It's not, and can't be turned into, the death ray that is sometimes portrayed in the media.

[Seret]

And if the goal is not to find a cheaper way to generate power, but to use an alternative renewable energy source and they are just going orbital to better bridge the night? If we do not only compare penny with penny but also pros and cons in general?

It still has to be financially viable, or else they'll never be able to raise the money to build it.

[Nibb31]

Remember, the beam from these things is massive. To do it right, you need a rectenna ten km on a side, meaning you can power an entire country with a fairly low energy density.

So how would it compare to a 10km² solar farm?

Seriously, we have no idea what impact it would have on the wildlife or on the ionization of the upper layers of the atmosphere. For all we know, it might cause a huge hole in the ozone layer or some other imbalance.

[Streetwind]

And how will we ever find out if we never try it?

FOR SCIENCE!

[Nibb31]

That's not how science works.

[FREEFALL1984]

Tidal energy is the future, its a little like wind energy but more reliable and with a much smaller footprint.

[Seret]

Tidal energy is the future, its a little like wind energy but more reliable and with a much smaller footprint.

It'll be part of the energy mix for those countries that have access to good tidal resources, but it will remain fairly niche. The available tidal resource just isn't enough to satisfy more than a small sliver of demand.

I don't want to seem negative about it because in general I'm a big supporter of tidal power, but you have to be realistic.

[NASAFanboy]

Fusion energy is the future, and it should be readily available by the 2020-2040 timeframe.

Right now, there is simply no use for space based solar power. Japan would be better off investing into fission power or covering one of its smaller islands that form up the chain (Iwo Jima, anyone?) and using it to construct a massive solar farm on the ground. That would be cheaper than launching less solar panels into space.

If space based solar farms ever become reality, they will be used for research and testing purposes, not for commerical uses on the ground. It is simply not practical enough and there are dozens of cheaper and more efficient alternatives. Like nuclear power (Look, Fukishima was hit by a tsaunami and a earthquake, and yet it didn't kill anyone or release any harmful dose of radiation.)

[Streetwind]

That's not how science works.

That's totally how science works. Form hypothesis, conduct experiment, analyse results!

(Besides, I was making a joke )

Tidal energy is the future, its a little like wind energy but more reliable and with a much smaller footprint.

Not a bad point, especially considering Japan has more ocean than land. Saw a funny concept a while back of a kind of long floating tube with joints that would get bent back and forth by the waves. The motions of the joints would be used to generate electricity.

It's not so good for nations like Russia, China, the US and other large continental countries, because transmitting electricity over large distances is a pain in the butt. Even in Germany, a country a mere 1000km from top to bottom, offshore wind park projects are facing their biggest problems in actually delivering the energy inland, where it's needed. Microwave transmission makes that a whole lot easier - you can beam it directly to the consumer. Or rather, a power station in the consumer's vicinity. Large continental nations simply can't do with tidal energy what they can do with something that arrives wirelessly from orbit.

[Streetwind]

Fusion energy is the future, and it should be readily available by the 2020-2040 timeframe.

We've been 10 years away from fusion for the past 60 years. We've yet to see an output ratio greater than 0.7, and to be commercially cost-effective it needs to be in the neighborhood of 15 to 20. I'm all for fusion power, but I'll believe it when I see it

[Seret]

Fusion energy is the future, and it should be readily available by the 2020-2040 timeframe.

No it won't. Even projects that are fairly well along (such as Tokamaks like ITER) won't result in a commercial power plant in that timeframe, even if everything goes perfectly.

Saw a funny concept a while back of a kind of long floating tube with joints that would get bent back and forth by the waves. The motions of the joints would be used to generate electricity.

That's Pelamis, it's being trialled up in Scotland. It's wave power though, not tidal. Different animals, wave power is similar to wind in that it's intermittent and difficult to predict. Tidal is intermittent but metronomically predictable, you can predict output years in advance so you can site your generators to smooth out the lumps.

Edited May 9, 2014 by Seret

[Faark]

If you have a very intense stream of energy towards earth you are probably able to weaponize it. So yes, i would expect such projects being realized.

[FREEFALL1984]

Microwave transmission makes that a whole lot easier - you can beam it directly to the consumer.

I imagine sales of tinfoil hats will soar... Also would you be able to use the microwave power plant to remotely cook popcorn.

[Streetwind]

I imagine sales of tinfoil hats will soar... Also would you be able to use the microwave power plant to remotely cook popcorn.

Completely new cinemas will be built, in which customers buy raw corn, receive a complimentary tinfoil hat with their 3D glasses, and enjoy an open air screening on the orbital microwave powered projector!

That is like, one of the most amazing mental images I've had this week. I'm literally grinning right now.

[NASAFanboy]

Even so, Japan would be much better off investing into fission power.

The world would be much better off if we invested into fission power.

EDIT: There appears to be a general misunderstanding. I'm saying Japan needs to build more nuclear power plants

Edited May 9, 2014 by NASAFanboy

[Nibb31]

Japan has had fission power since the 1970's. Fukushima is fission power.

Maybe you mean fusion power, but it simply does not exist yet, so there is nothing to invest in. Fusion has always been 20 years away ever since the 1960's. It's a bit like Mars landings and Moon bases in that respect.

At any rate, it takes 20 years to plan, approve, design, and build major construction projects like airports or nuclear plants. So even if the technology magically became available next year, you won't see an operational power plant before 2040. It would still take decades to make it "widely available".

[Jouni]

The problem with fission power is that it's way too expensive now. With all the safety mechanisms required, new nuclear power plants are no longer economically viable. Even wind and solar are starting to be cheaper.

[KerbMav]

Japan would be better of using (more?) of its very long coast line for tidal power.