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Deploying Solar In California's Urban Areas Could Meet Demand Five Times Over
Lucas123 writes: About 8% of terrestrial surfaces in California have been developed, ranging from cities and buildings to park spaces. If photovoltaic panels, along with concentrating solar power, were more effectively deployed in and around those areas, it could meet between three and five times what California currently uses for electricity, according to a new study. The study from the Carnegie Institution for Science, found that using small- and utility-scale solar power in and around developed areas could generate up to 15,000 terawatt-hours of energy a year using photovoltaic technology, and 6,000 TWh of energy a year using concentrating solar power technology. "Integrating solar facilities into the urban and suburban environment causes the least amount of land-cover change and the lowest environmental impact," post-doctoral environmental earth scientist Rebecca Hernandez said.
Calling any party/politcian from the US as socialist when they don't even have true single payer universal healthcare is just laughable. Our right wing parties in Europe are more socialist than Obama or the Democratic party of the USA.
You sell any daytime excess back to the grid during the day, and draw back at night
You make it seem that the same energy that you sell during the day is bought back at night. That is not true. The electricity you sold during the day is used during the day and reduces the production requirements for conventional electricity produces. The electricity you buy at night is produced by those conventional producers. Someone still has to produce the tlectricity you use at night and it will not be another PV user because it will probably be night there too.
see also Tesla's new home battery pack stuff?
Lets install a $20,000 battery in a house and replace it every ten years.
It's odd how it seems like most posters are trying to find problems rather than trying to find solutions.
It's odd how it seems that some people solve 50% of the problem and leave the other 50% to other people to solve. There are solution and the main one being storage. There is too much emphasis on electricity production technology and not enough on storage.
It's almost like you don't want solar power, when 'solar' is one of the things California has so much of.
The problem is that California has almost no "solar" at night and little is being done to compensate for that. It does not matter if 4x the required energy is produced by solar if only a very little of it is available at night.
The article makes it look like solar is the solution to the energy problem. It is part of the solution but more work on storage needs to be done.
I'm sorry that I often forget my disclaimers like 'excluding outliers', 'average situation only', etc...
As nospam mentioned, there might be a problem with your house. Now, I'm no expert, but I'd need some more information to do an assessment:
square footage of the south facing side of your house
annual kwh usage
For example, I'm an outlier. I'd have to completely cover my south-facing roof with solar panels to match my usage, but I live in Alaska.
Some things that might be 'nice to know':
Have you ever had an energy audit of your house done? Do you know what the R-Value of your walls/roof is? What's the SEER for your air conditioner? If you're using more than 3X the power that could be generated by solar for your roof, you may be better served by installing more insulation, replacing a marginal HVAC system with a more efficient one, etc...
Heck, I pointed out that solar panels can help cut HVAC requirements by their mere presence - they're not normally installed directly on the roof, so that few inches acts as insulation(and can even create a heat chimney effect to keep things even cooler), preventing direct sunlight from heating the roof extra, increasing cooling needs.
I don't read AC A human right
If you offset the panels from the roof by a few inches, the cooling demands will likely go down. The sun will heat the panels rather than the roof and convection will carry that heat away.
This study claims a reduction in carbon emissions from solar power but I've read studies that show increased carbon emissions from solar power. Why is that? Because solar power is very poor at matching when people use power. Sure, people tend to turn stuff off at night when the sun is down and turn them on when the sun shines but the load curve seen by utilities shows a peek power usage at about 6:00PM, when the sun is setting and solar power has already begun to wane.
How does this translate into increased carbon output? When solar power wanes there needs to be a power source that can be brought up to power quickly and still be inexpensive enough that it is economical. That is where natural gas comes in. Instead of using highly efficient combined cycle power, which takes hours to come up to power, the utilities use natural gas turbines. Combined cycle power plants get about 60% efficiency, gas turbine power plants might get 40%. Turning the turbines off and on burns more fuel, reducing the effective efficiency.
So rather than using a highly efficient combined cycle power plant a utility that must accommodate the quickly changing output of solar power must use less efficient gas turbines. The more solar power on the grid means more gas turbines. More gas turbines means less efficient use of natural gas. Therefore there is no net reduction of carbon emissions from use of solar power.
Then comes the argument for storing the solar energy for use when the sun does not shine. That adds cost. We have nothing that can store electricity that is cheaper than burning natural gas or coal, using nuclear power, or using hydro power. If solar power is to become cheap enough to compete with coal and nuclear then we need a means to store electricity that is cheap.
The problem then comes in that any technology that makes storing electric energy cheap also makes coal and nuclear power cheaper. Then why not just make solar power cheaper? Because that will never solve the problem of the sun going down.
Solar power is a dead end. Solar power would have to be cheap enough to make up for the costs of its manufacture and storage as well as compete with coal and nuclear. While we might run out of coal in 300 years we just cannot run out of nuclear fuel, it is just too common.
Then there is the environment disaster that is caused by the manufacture of photovoltaic panels. Making them requires significant amounts of water, toxic chemicals, and lots of energy.
Solar power is not the answer. Nuclear power is the answer. I know someone is going to point out the nuclear waste that comes from nuclear power now. My answer to that is Waste Annihilating Molten Salt Reactors. These things eat radioactive waste. If it is radioactive then it is fuel. If it's not radioactive then it's not waste any more, right?
I am armed because I am free. I am free because I am armed.
One of the reasons Denmark can run on wind (currently 39% of their total) and solar power (500 MW total from 90,000 private installations according to wikipedia) is that we have installed multiple DC transmissions lines between Denmark and Norway, and hydro-electric power is by far the most responsive to changing load.
On the west coast mountains we have storage dams where surplus power can be used to pump up water during periods of surplus production and then let down again when Denmark, Sweden or countries further south need some extra power.
From http://en.wikipedia.org/wiki/P... you can see that this is _by far_ the largest grid energy storage form, accounting for more than 99% of the total capacity worldwide.
The total efficiency (70%-87%) is quite good, which means that this is not just a good idea but can pay for itself anywhere the difference between peak and off-peak energy costs are larger than the ~20% that is lost to pump friction.
Terje
"almost all programming can be viewed as an exercise in caching"