Originally posted by Off_The_Street
Mirrors in space.

Theoretical insolation in space is higher than the maximum here on Earth, but not by much:1.3 kW/m^2 as opposed to about 1 kW/m^2. If you wanted to send a concentrated beam to the Earth equal to, say, the output of Palo Verde Nuclear Generating Plant (38MW) , you would need a mirror 6,100 feet in diameter and a system where there was no efficiency loss at all.

a) 6,100 feet in diameter is nothing if you do it with mylar, although such system would experience a force equivalent of 6 lbs due to the solar light pressure and will need to be stabilized

b) if there is no clouds (!) the efficiency can be rather high

And, of course the beam of concentrated heat would vaporize anything it touched on Earth

You don't have to concentrate it on a small spot, by any means. Yes, it will still be pretty dangerous.

so you'd probably want to convert it into microwaves

Unnecessary.

If you figure the amount of mass involved for the mirror and support structures (even assuming aluminized mylar over an aerogel or buckytube frame), as well as the computers and thrusters to keep that big honker pointed right, and the present cost of using something like the space shuttle fleet to haul up the pieces and put it together, you could probably get a half-way decent 38 MW power plant in space....

...for about a trillion dollars.

I disagree. Missions like that can be totally robotic, especially if this is built into the design. One can use small affordable launch vehicles. Hell, forget trillion bucks. For a few billion, the Ukranians will build this for you

In addition, this doesn't have to be a monolithic mirror and can be a swarm -- less probability of a single catastrophic failure.

Originally posted by LazarusTheLong
how about the paintable solar cells on a hybrid biofuel car in the future?
(where the biofuel generator isn't used as a motor, but an alternator to charge the batteries). Maybe even put a little wind turbine in the air ram area (watch out squirrels) to add to the mix. the total emmisions would be from a small biofuel generator/alternator, instead of a huge gas motor.

Regarding the solar-cell-paint job/biofuel combination, hell yeah!
However, what would probably give the most bang for one's buck would be something along the lines of this:

The engine has two alternate power sources:

For daylight travel in a sunny enough area, you could use the solar cells complete power, and have the option to partially compliment it with biodiesel to make up for cloudy days or when you just need extra speed.

For night time travel, you can switch the engine over to pure biofuel, that way you don't have to worry about running out of "juice" except in the literal sense.

An alternate switch could divert all the solar power to charge the battery in the event you need to get a jump.

OR You could cut down on the amount of kinetic energy loss by using the solar cell to exclusively power the battery, while biodiesel does the power of powering the engine, allowing for less "work" by the engine to push the car forward.

However, I like the first option better, because if it's cloudy for too long, you can end up losing out on battery power.

As for the fan, you'll have to ask our engineers, but I'm pretty sure the added drag to the car would result in a net loss of energy.

for non transportation needs, we just need to have less environmentally damaging methods available, and time is not so crucial (except for the global warming thing)

Here is a radical idea similiar to the orbiting solar cell idea...
one for OTS... and any other engineers or scientists.

A test on the space shuttle found that a conductive wire extended from the shuttle conducted such a massive amount of electricity that it not only burned it thru, but caused the broken wire segment to illuminate brighter than many stars for several hours (visible from the ground like a giant light saber)... thereby proving that they can generate whatever electricity they need in space by sending out a very long wire to conduct electricity from the magnetic belts of the earth itself.

why couldn't this same method be used to beam down energy in the form of a laser (like military field equipment does) or microwave?

we could just have orbiting satelites that are converting and sending free energy for as long as the world produces a magnetic field?
(*source numeous discovery programs) or would this be a problem to the earth that we are trying to protect?

While an orbiting mirror or a circuit between magnetic poles would produce energy for the planet I wouldnt trust the human race as a species with it.

The military applications of a giant mirror orbiting in space capable of a concentrated microwave beam or even UV beam would be enormous. Flicking the mirror to wipeout a "rogue state" would literally take seconds with no remaining radiation like a nuclear weapon would. I for one would not trust us to have such a device.

The same can be said about a circuit between both magnetic poles. If that was to be disrupted or destroyed the entire planet would be dead in days. Would we, as a species, be confident that our tinkering with the magnetic field around our planet would not cause this? I wouldnt risk it no matter what. Look at what we've done to the Ozone layer for example.

Its a shame and testimony to our species that such clean and apparently sustainable energy sources are out of reach simply because we cannot be trusted.

[edit on 9/4/05 by subz]

a little addition to reinforce the arguement against the nuclear fuel option...
the landslide in Krgystan that took out a nuclear fuel rod storage area, could contaminate a good portion of central asia.

If we can't pay the price, then we shouldn't play the game...
and no one can pay the price of a nuclear accident.

I really hope they can hold back the contamination from the river that is washing thru, or else an awful lot of people will have to be relocated, as well as the entire length of the river. It was probably a source of water for many villages down the way... those will have to be relocated also.

the damage from this incident will eventually add some more radioactive danger to all our lives.

From agricultural sources - the coppicing of willow trees specially grown on farms, plus the production of gas from farm slurries, sewage sludge and abattoir waste. The report states that the conversion of a tenth of the 7,944 hectares of farmland to coppice would produce almost 8,400 tonnes of dry wood chip each year, more than enough to fire a power station producing 9.6 GWh/year, the total electricity requirement of the town, as well as a considerable amount of hot water which could be used to warm workshops, greenhouses, homes and offices.

Yes, you are right....Biofuel will not sustain our current use, way of life. but it does provide fuel AND heated water at the same time.....sustainably.....

I guess that was the point I was making.....Europe is way ahead of us in EFFICIENCY and dual purpose energy resources.

If we didn't export our water,fuel, and soil, we could have a biodiesel station in every town.........

Hydro-electric... are you kidding!?!?!?
Please tell me you're kidding! The environmental and ecological impact of a dam effects the entire watershed of the river, upstream and downstream, changes the very land itself, and the erosion damage alone is unthinkable.

This is bollox, yes it can cause all these problems but then there are some engineers that should be hung out to dry for it, if well implemented it can cause only small amounts of these problems especially if plans are put in place to offset the econolgical damage. I live in British Colombia(Canadian province) where where our electric co. is called B.C. hydro due to our dependence on hydro power. While it does cause problems they are minor, problems occur when people make hydro dams where there isn't the waterflow to justify it and don't make compensations for ecological damage. The problem is that not a lot of the world is appropriate for this but people build it anyways because it's so cheap, cheap enough that Alcan aluminium operates in B.C. for low power costs even though there's no aluminium. For example we pay around 6 cents per KWH next to an average 8.3 cents for the U.S.

Coal Power Plants, on the other hand, are believed to account for 64,000 deaths each year (some rate it as high as 100,000), 159,000 emergency-room visits, and 6,000,000 asthma attacks EVERY YEAR.
(Source Article)

Hydro-electric Dam Failure actually caused the death of 15,000 people in India, 1979. This is one incident, hundreds to thousands more have died from other failures.
(Source Article)

Natural Gas accidents account for over 100 deaths per year, worldwide.
(Source Article).

One thing you're forgetting is that all three produce more power for the world then nuclear, while I agree that nuclear power is demonized they aren't as good as you're claiming either, if for no other reason then the fact that we haven't been through the thousands of years of sorting the radio-active waste to be sure. I think the best way of setting up the cost/benefit of each is to compare the monetary cost/lives lost/KWH produced.

Wave Distortion - Wave Generators have the effect of significantly lengthening the wavelength and reducing the height of the waves which pass through them. This causes the coastline to be less affected by erosion, which is good in some areas, and bad in others. So location is a major factor.

Another type out there is the tidal generators which are quite different and act much more like two way hydro dams, one of these is active in Nova Scotia(Canadian province) where some of the biggest tides in the world occur.

It seems to me that biodiesel may well be able to help if not solve the transportation issue, however there still remains the spectre of cost, will we be able to afford to commute to work every day? If not then life will start to change dramatically and even if you could afford it our lives should change dramatically. Quite simply we have lived too long in a world of convenience were some of the least efficient things get by because it's convenience and easy. Transport trucks and Jet airplanes should not exist for commertial transportation, the maintenance costs are simply too high. The only reason the more appropriate system, trains, hasen't taken over is because the goverment pays for roads and helps for airports, trains have to pay their own way(very expensive with their grade restrictions) and they are still competitive. I think that given the nessesary electricity it would be entirely possible to have all transportation run off trams and trains. Trams would replace buses in current public transportation schemes, and trains would insure that none would go further then 10km or so without using one as they would be faster but with less stops. Even based off of current electricity production methods this would drastically reduce energy consumption in the transportation sector. Further forcing all energy to be taken from the energy grid would make it much easier for goverments to control pollution/sources... If providing electrical power wasn't already a goverment responsibility it should be made one because of the need for accountability in this sector and helping to encourage investment in new technology. An electrically powered economy would require lots of investment before the fall of the oil based one but is the only on that I could see being capable of similar capacity. The only question that could remain is what to run the power plants on, for one solar roof tiles should become available as well as the capacitors on a local level to take that power. However this is far from being enough, responsible hydro is useful but mostly depleted with many regions going to less responsible projects it too would need something to suppliment it. Geothermal is promising but must be contructed near faults where hot rock is close enough to the surface without there being geographic instabilities(Note we have yet to drill right through to magma so far it has to come to us). I think the best hope of meeting the energy demand is fusion which has been progressing slowly but surely for quite some time, I think we've hit the break even point. ITER is an international organization who's planning on building a reactor that will produce more power then it uses in Canada, Japan, Spain or France. Once started it will take 10 years to contruct, given another decade or two commertial fusion plants should be viable, this one costs around 5 billion not too bad for the size and experimental nature. Cold fusion has been largely disregarded and other designs have yet to prove their feasability. Often seen as one of the technologies that are always over the horizon I think they may finnally be getting to the end of the road.

whoud it be possible to exploit deep sea currents a lot off ocean's have deep cut out trences it whoud be possible to create stops in those trences and build giant turbines working on the the force off the water stream , whe coud also build constant waterflows based on the temperatur diferences between diferent parts off the ocean , it probably whoud costs lots off money , and it whoud need lots off maintenance but the power source is unlimited , and the turbines coud realy have giant proportions , as the currents are verry strong and verry large on somme places , it ould be better to construct 3 or 4 giant project then 1000 off smaler ones .
Maybe somme engeniers on this site have Idee's about dimensions and possiblity's

According to an environmental science course I took in university, the best alternative in the future is still nuclear energy.

Uranium is abundant on the Earth, and its potential for generation of energy is HUGE. Small blocks of uranium can provide enormous amounts of energy.

Many other alternative forms of energy simply cannot provide enough energy to meet out demands, and most have their drawbacks too.

Nuclear waste can be treated in two ways: re-enrich, or store it away in some safe place. As long as it's stored in a safe and unpopulated (in terms of organisms in general) place, it's all good. Properly disposed nuclear waste isn't as bad as some media portrays it.

Modern nuclear powerplants are also designed very safe. Chenobyl was not. That, and the fact that the Chenobyl reactor was manned by irresponsible employees, caused the Chenobyl accident. Other than that, nuclear reactors are very safe, not nearly as bad as portrayed by certain media.

Some drawbacks include crazy politicians making nuclear warheads and possible leaks during re-enrichment processes, but overall, nuclear power is our best choice for the near future.

As for the far future, I see potential in nuclear fusion reactors.

Hydrogen is a good medium for storing energy in cars, etc.

[edit on 20-4-2005 by Taishyou]

Uranium is abundant on the Earth

If you consider 200 years of supply abundant(and that is at current consumption levels circa 1990s and doesn't take into account Chinas huge move towards this energy source) plus there is the problem of Waste. That is why Fusion is ideal in my mind(even though its 30 years from commercialisation) as the waste can theoretically be completely eliminated with the use of the right materials. It's a stopgap(and risky one at that) measure at best. I do agree the safety of these plants has gone up as they have developed, but safely disposing of the waste is still the biggest issue in my mind.

The central problem is oil for transportation.

By the laws of physics and chemistry, there isn't anything better than liquid hydrocarbons for transportation. There isn't any other source with as good an energy density and transportability and which allows as good power output. (Nuclear cars are obviously
idiotic for safety reasons).

Now, in the US most electricity is from Coal, Natgas and nuclear.

What's inevitably going to happen as oil costs go up is increased demand for the hydrocarbon sources as transportation, firstly natural gas but perhaps even transformation of coal. We will then need some replacement for the electrical power. I agree with Mr engineer here---nuclear is the best of bad alternatives when you work the numbers. Science and nature is inherently quantitative. We just have to butch the freak up about the waste. There will be problems, but we have other problems ALREADY. Why are people so blase about those dying and suffering from air pollution TODAY, and they get freaked about some hypothetical radiation accident in the future?

A question to the chemical engineers out there. Optimal fuel for vehicles and aircraft are liquid hydrocarbons---they have to have the right ratio of H to C.

Now nat gas is CH4---has too much hydrogen to be liquid. And coal is just plain C, not enough H. Seems reasonable that there must be some way to combine them to make high-quality liquid fuels, which is what we need. Is there some thermodynamically efficient way to do this?

We have plenty of wafer-producing industries in the US- if only they had a little of that gas,oil,coal,and nuclear subsidies money - they would be able to flourish............


GERMANY: April 26, 2005


FRANKFURT - Solar energy company SolarWorld is on track to meet its target to raise profits and sales 40 percent this year following a good first quarter, its finance head said on Monday.


"We will definitely not disappoint the capital market with our first-quarter figures," Philipp Koecke told Reuters.
Demand for solar equipment is huge and the company is sold out for 2005 and almost sold out for 2006, Koecke said.

He added that silicon supply for 2005 and 2006 was almost secured. The company said earlier on Monday it had agreed a 10-year contract with Wacker GmbH for the silicon maker to supply it with solar-grade silicon from 2007 to 2017.

Shares of SolarWorld, which makes solar wafers, cells and panels, were 1.4 percent higher at 98.09 euros at 1024 GMT, outperforming a 0.3 percent drop in the TecDax index.

SolarWorld has benefited from booming demand for solar energy that helped it double sales to almost 200 million euros ($261 million) last year and achieve a net profit of 18.1 million euros that beat its own forecasts.

The solar market currently supplies a fraction of 1 percent of the world's energy needs and is worth an estimated $7 billion annually. The industry may increase that proportion to 8 percent by 2030, according to the European Renewable Energy Council.

Given generous subsidies from some governments -- notably Japan and Germany, the world's two biggest producers of solar power -- demand has soared for the panels that harness energy from the sun to provide electricity without emitting carbon.

sardion: good post
that is the main reason that I introduced this topic...

much of what we see as challenges are actually economic opportunity...

I will paraphrase a few points from your very informative article... and use the analogy of what it would do in america.

using alternative energy is a great thing if you have the money to invest in the infrastructure.
Since Germany decided to go green, it has boosted the economy by leaps and bounds... and they aren't even manufacturing any of the componants...(america is..hint hint)

germany produced 450,000 new jobs with the new processes and methods of energy production (more taxes)

toyota increased spending on environmental improvement technologies to 201 billion....
they earned an additional 260 billion due to positive PR for the effort...(59 billion net profit)

california discovered that using "green" methods of building construction cost an average of 2% more than normal building methods...
with a 50%-1000% return on the investment...(depending on what variables you include)

granted... these all cost money to initiate... but it is a proven great investment with a great payback...
many millionaires scramble to find an investment that will give a solid 10% return...
I think they are either blind, or stupid... or just willing to settle for less...

check out sardions article... it is very enlightening to those that say... "all that can be done is being done"... BA

Texas A&M has the captured files of Nazi methods for production of liquid hydrocarbons from coal. There are actually two methods. The USA has the greatest reserves of coal in the world. During WW2, the Germans actually used both methods and produced lubricating oil, gasoline and heating oil. In fact, the lubricatiing oil they produced was marketed in the mid 1970s by Mobil Oil under the brand name "Mobil One". You might be familiar with it.

During the 1950s, the US goverment actually built a refinery using these methods and produced gasoline which would have cost less than $00.20 cents per gallon. Actually,it cost much less than that but you would not believe me if I gave you the figure. Under pressure from Big Oil, the Eisenhower Administration dismantled the test refinery. If you don't believe me, and you shouldn't, write Professor Arnold Krammer at the Modern German History Dept., Texas A & M and he will drown you with information of this subject. That is unless Vice President Darth Cheney has silence him in one of those pincher-neck grips.

big oil is the enemy...
oil is still around, they just want more profit from it... and are willing to spend millions/billions in political pockets to get new friends that support them.

anyone else notice the oil has suddenly become "rare" and expensive ever since we have a texas oil man as president?

time to take advantage of the window that was opened and promote more environmentally friendly options that WERE too expensive to consider,
but now....not so much...

I still think the ultimate would be wind, solar, and water, since they have very little negative impact upon ecosystems. (yes, "hydroenergy" can be done friendly, but rarely is)