Why We Have No Wind or Solar Power

[NeilBlanchard]

Hello,

Have you folks seen the proposal in Scientific American? It uses a large amount of solar PV and heat systems in the southwest of the USA to generate up to 69% of all the electrical power for the entire contry:

A Solar Grand Plan: Scientific American

High voltage DC transmission lines would connect the generators to the large city nodes. The excess power would be used to compress air into underground caverns, and then when needed, the air pressure would be used to spin turbines and generate it near the consumer.

Also, molten salt could be stored underground near the solar heat plants to store excess heat for days of power w/o the sun.

Add to this, dispersed wind farms from Texas to the Dakotas, and add biomass, geothermal, offshore wind power, tidal power, wave power, and we could have a huge amount of power -- WAY in excess of what we would need.

So, mix and match, disperse, diversify, distribute, conserve -- this alone could cut our needs in half! Almost zero carbon emissions, and zero mercury, and none of the myriad of other pollutants, no fissionable or radioactive materials to leak into ground water or terrorists to covet -- we don't ave to import anything, and we don't fund unfriendly governments. We provide jobs that cannot be globalized, and we have no need to fight over oil, or natural gas.

Lessee -- it pretty much solves at least three major problems: energy, security, and economic stress.

[Duffman]

Neil,
I am not going to rehash all the issues we discussed in the other thread, the main issue being intermittency. You are basically proposing that we power the industrial heartland of the U.S. (NY, OH, PE, MI...) with a multi-thousand mile ambilical cord from the windfields of the midwest and the sunbelt of the south-west. You see no security issues here? Do you think those communities that are at the end of the cord will find it acceptable that they are always the butt of the brownouts when energy shortages occur?

[Big Dave]

DC transmission from the High Plains to the Great Lakes? Thousands and thousands of eminent domain cases. Thousands of appelate court cases.

[NeilBlanchard]

Hi,

Did you watch the video on what Germany is doing? Geographic distribution, and source distribution answers the "intermittent" issue.

A strong, flexible and robust grid is a key part of the answer -- if we get energy independence that employs lots of people, stops the need for fighting over oil, and drastically cuts pollution. I think it can happen, and I think others will agree with me.

Wind farms can be offshore of both coasts, and wave and tidal power systems are also on the coasts. Biomass can be used in many other places, and so can geothermal. Seems to me like all areas of the country/world have plenty to add to the mix!

[trebuchet03]

Originally Posted by Concrete

new large bladed turbines do not have this issue
ones near here are held to 28.8 RPM - easily visible and avoidable by birds

It's worth pointing out that these large bladed designs have really high tip velocities.... Which leads to an unfortunate limitation of scale as you get nearer to the sound barrier.

High Altitude It's the future

[Concrete]

Originally Posted by NeilBlanchard

Hello,

Have you folks seen the proposal in Scientific American? It uses a large amount of solar PV and heat systems in the southwest of the USA to generate up to 69% of all the electrical power for the entire contry:

A Solar Grand Plan: Scientific American

snip

Lessee -- it pretty much solves at least three major problems: energy, security, and economic stress.

Neil,
I like this as a thought a experiment
but in the real world it will have some issues

DC lost out as the power of choice for very good reasons 100 years ago
Cadmium in PV is not much better than mercury from coal in my book
+3-4 cents per kWh for cavern storage is hard to support 11 cent rates
most of all it starts in 2020 and changes 69% of power distribution in 30 years
I has taken a 100 years to build the system - it will take that long to change it
don't get me wrong - I'm for it - but it must earn its way into the grid
if it doesn't it will be an economic burden of good intentions

BTW
all the best Ideas are always 10-20 years away
I have been dreaming of viable PV for... +25 years

Hey! weren't we supposed to have jet cars by now

[Duffman]

Its still all theoretical! Germany still uses conventional sources for 85% of thier power, so they have proved nothing in that video.

Power generation, Germany

Denmark the world wind leader is only at 20%. Because they are a small country they just lean on their neighbours to export and import their intermittency problem.

Wind power in Denmark - Wikipedia, the free encyclopedia

[conradpdx]

Really as I see it the best way to vastly expand renewable energy is to ease up on the restraining laws and policies for property owners in the US.

For example, with net metering of solar panels you cannot make a profit on your solar array as an individual. The best you can do is get to Net 0, which means you create as much power as you use. If you build a system that generates a surplus of electricity over the the agreed time span between you and your electricity provider, you have just donated power you your local supplier. Likewise, your provider will demand that you install a special meter for the service, even though you can set up a panel array and simply convert it to AC and plug it into an outlet to move your meter backwards, which is also illegal without contracts with your local power provider.

These are unacceptable, if we're really serious about getting off oil and expanding solar and wind power then some of these little steps when combined with the current (and hopefully even better future) incentives would create amounts of power that these large scale farms would be hard pressed to match. And paid for with the dollars of private citizens.

The benefits of such a system would have a number of positive effects. A decentralized grid, faster pay off periods for the owners of the systems, long term revenue potential for owners of such systems, conversion of useless spaces (roof tops) rather than using up millions of acres of undeveloped land, lessen power losses from travel, and I could go on.

Really the whole thing is just frustrating, especially since the rules are set up not to help people but to benefit the power providers. The powers that be are currently only playing lip-service to the whole concept, but really they need to suck it up a little and let us have a bite.

[jamesqf]

Originally Posted by NeilBlanchard

Recently, and MIT lab developed a way to drill a 7-8 mile deep hole relatively easily; using a gas cutting head rather than a mechanical one.

So I can call up my local drilling company and hire one of these, no? Until then, it's still theoretical/prototype stuff. Might work, and certainly worth looking into, but we need technology that we can build today - or that should have been built 20 years ago - not "we'll have the bugs worked out in a year or two" pie-in-the-sky.

The heat down that deep is pretty darn close to inexhaustible.

It's not a question of it being inexhaustible or not. It's a question of how fast the heat will flow through rock. So you drill a well: that's a narrow cylinder. Pumping water down it will boil the water, but will also cool the rock at the surface of the cylinder. That sets up a gradient, so heat will flow from the surrounding high-temperature rock, but since the rock is not a good conductor of heat, it will not flow very fast. For any particular situation - size of well, temperature at the bottom, etc - you will quickly reach a steady-state, where heat flows at a constant rate, which generates X amount of steam and so some fraction of X MWatts of electricity. That's why the geothermal plant up the road only generates 90 MWatts (or whatever the number), and not enough power to run the whole West Coast: because that's the amount of heat that flows into the geothermal area.

Any engineer could easily plug numbers into the relevant equations, and figure out how much power you can expect to generate from a given well. The drilling people can give you a cost on the well, then you need generators, ongoing maintenance, and so on. Do the math, and figure out how much a MWatt is going to cost.

[NeilBlanchard]

Hiya,

That's what I thought when I first heard about high voltage DC transmission line, too -- but they are in fact very efficient, and they are real. There are at least three working HVDC transmission system already, so forget what you think you know on this!

How is a working system that is reliably supplying 15% of the electricity for a major European nation "theoretical"? If they can improve it and enlarge it, it will supply all their power -- if it was "theoretical", why would the German engineers even think of implementing it?

Can you call your local builder to construct a nuclear power plant for you? The temperature at ~8 miles is ~300C, and sure, you could not put an infinite amount of water down there, but the surface area is pretty big, even if you only count the hole itself; and leave out any cracks or fissures.

Science Friday Archives: Geothermal Energy