Capital Costs of renewables

Hard to say. Right now, PV which is the least maintenance intensive, isn't very efficient. Should that efficiency ever grow say 3 times or more, then it could be very viable. It would then probably be efficient enough to make hydrogen from water with any excess electricity, and make electricity with a fuel cell when needed. Maybe even enough excess to keep your Tesla charged.

Please do not count solar out. Advances in science could make it very competitive.

 

Not really possible PV is inherently inefficient.

 

The ONLY solar I support are the new organic ones they are just beginning to develop. Traditional panels are horrible for the environment because they utilize REE and other metals that require hydrometallurgical mining or vast strip mining operations. China has devastated their land in just such mining operations to get the very materials that are required for solar panels. At best they also only last 25 years and that is an optimistic estimate that no engineer actually seriously believes than can make. In fact solar panels world wide have failed much sooner than their projected life spans.

Also, there is a limit to how much solar power can be collected. The theoretical efficiency limit is 85% and on average you get around 200 watts of power per m^2 which is not a lot of power at all compared to other forms of fuel which have much higher energy densities. Solar power in fact is one of the least energy dense forms of power around.

Even at max efficience they will NEVER be able to provide enough power for commercial operations. They could easily proved residential power needs at least in sunny parts of the country though, that I have no doubt of at some point.

Nuclear is really the only choice right now and the Gen 3s and 4s last 60 years and with a refit 120 years.

 

Are you saying the efficiency could never increase?

In my opinion, they are so inefficient, there is a great deal of possible improvements to be made. Never underestimate science.

 

thanks for the tips, wife is weighing in on this now and we have decided to go with a medium sized commercial green house kit so she will have room for her decorative plant gardening endeavors, move the compost pile into it to help a bit with the heating and go with a ceramic for the cold nights. I still might do the 55gal drum routine and a home built collector just to help on the milder nights. Every little bit helps and I will build the collector and heat exchanger using junkyard technology as much as possible

 

Well, considering is you only assign 100 W/m^1 of average energy and 40% efficiency to electrical conversion, you would have over a 1 Gigawatt system Storing and releasing the excess, say half of it, probably amounts to only a 50% efficiency of that (70% store 70% release). So 1/2 GW + 1/4 GW still gives us a 750 megawatt system for a square mile. Los Angeles peak energy requirements is not probably around 7 gigawatts (6.165 GW during the 2006 heat wave), so less than 7 square miles could supply LA with electricity. For those wanting to go to a hydrogen fuel economy, 44 KWh of electricity makes hydrogen with the energy equivalent of 1 gallon of gasoline.

I agree we should invest in nuclear, but it is expensive too. Solar keeps coming down in price, which alone isn't enough. We need it to be 40%+ efficient in my opinion to be cost effective for the real estate it occupies.

 

The typical efficiency of solar panels is about 15%. 19% is commercially available. The highest efficiency panels made (not commercially, just experimentally) are in the 40% range.

http://pureenergies.com/us/how-solar-works/solar-panel-efficiency/

 

You may find that you will have a bigger problem keeping your greenhouse cool than you will keeping it warm. In the warm months the temps go way up and the humidity drops to next to nothing. You might want to cobble together a evaporator cooler and invest in a shade cloth. A greenhouse is easier to keep warm when it is full of plants. Or spray it down several times a day...or look into one that you can raise the sides.

 

Those numbers are made up though. Real life examples fall far short of the rose colored predictions of the solar power people.

http://www.phoenixsolar-group.com/b...see.8abb13d2-81f4-405b-ae45-204e1a75320f.html


The Volkswagen Chattanooga Solar Park occupies 33 acres, or half of the 66-acre land parcel adjacent to VW’s state-of-the-art manufacturing plant. The solar park contains 33,600 solar modules from JA Solar designed to produce 13.1 gigawatt hours of electricity per year -- equivalent to the energy consumed annually by around 1,200 homes in the area.
The electricity produced from the solar park is expected to meet 12.5% of the energy needs of Volkswagen’s Chattanooga manufacturing plant during full production and 100% during non-production periods. The plant covers 1.9 million square feet and employs more than 3,000 people who manufacture the highly-acclaimed Volkswagen Passat sedan. For Volkswagen, the solar park in Chattanooga will rank as the automaker’s largest photovoltaic installation worldwide.

That is a horrible use of land. You need 5,000 acres of solar panels to produce the equivalent of one nuclear plant which takes up only a few square miles. That is assuming peak effeciency all the time. Since the sun doesn't shine 24 hours a day and you have less energy in the mornings and evenings you would actually have to have 20,000 acres of solar panels to produce what one nuclear plant does. The only thing that solar power can realistically power is a residential home in a sunny climate which has been proved with people being able to sell back power to the companies. Outside of that solar power is a monumental waste of time and space and money.

Germany spent almost $300 billion dollars on their massive solar energy campaign and the best they could do was 50% of energy production for only two hours on two seperate sunny days in August. Germany has among the highest energy rates in the EU. Compare that to Scandinavias new nuclear reactor which came in WAAAAY over budget and its still cheaper than Germany's solar energy. Germany has since abandoned their idiotic chase after solar and hopefully they will stop it with their anti-nuclear idiocy.

 

I don't like the way they used land better suited to forests, parks, farming, etc either.

I would like to see solar in wide use when the efficiency is increased, and placed in deserts. Not forested areas.

We can start now with current technology with the expectation that more efficient solar cells can replace them. However, I don't want to see any of the costs subsidized with tax dollars.

I also think the power companies should get together and create a national DC intertie.