This is a sample guest message. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!
Aren't the Chicoms drilling (or going to) on the Cuba side of the Florida strait??
Only if you pencil whip the numbers within an inch of their lives, and compare apples to oranges. Yes, a home-owner installed system that provides much of his electricity for personal use at his own home in Arizona MAY break even economically within 10-15 years when compared with the cost of commercially available electricity. And if we really stretch, then a hyper-efficient solar plant installed in the Southwestern US may be able to put some electricity onto the grid for the same cost per kilowatt hour as a gas/coal plant. But that's not the same thing as saying that solar energy can really compete economically with other fuels at a commercial level on a nationwide basis. There is just not enough sun in most of the US to even consider it a possibility. It. is. not. going. to. happen. Same thing with wind - locally, where the wind blows and when the wind blows, maybe it can break even. But as a nationwide replacement? Non-starter.
Yes, you are absolutely correct - today. That's why I set my threshold at 50-100 years. Fossil fuels will not always be this cheap, and soon we'll be down to coal and gas, which are not nearly as convenient for portable power. At that point, electrics will get a huge boost (out of necessity) - liquefied fuel from coal or gas could provide a stop gap, but in 100, 200 years, everything will be electric. What say we meet back here in 2210 to settle it?
Yes, you are absolutely correct - today. That's why I set my threshold at 50-100 years. Fossil fuels will not always be this cheap, and soon we'll be down to coal and gas, which are not nearly as convenient for portable power. At that point, electrics will get a huge boost (out of necessity) - liquefied fuel from coal or gas could provide a stop gap, but in 100, 200 years, everything will be electric. What say we meet back here in 2210 to settle it?
The problem isn't the efficiency of the PV cell, which of course is the sexy part of the equation that researchers just looooove to dig into right away. Oooh - exotic materials! New deposition processes! Publish, publish, publish! Big deal.
Even if I handed you a design for 100% efficient cells tomorrow, you still wouldn't be able to build a commercially successful, cost competitive solar plant outside the Southwest. For example, in New York, sunlight is just too rare (~6 hours per day on average) and too diffuse (324 W/m2 on average) for the efficiency of the PV cell to matter. 100% of a small number is still a small number - an average of 1.9KWh/day/m2 in this case. Therefore, the only way to grow the power output of the plant is to make it larger, and there goes your cost competitiveness, especially after you fight off all the NIMBY lawsuits (to say nothing of your backup plant or storage system for when the sun isn't shining). Now if you could build a PV cell with 300% efficiency, you might be onto something....
Photosynthesis captures only ~5% of available sunlight, so you're far better off covering your available land with PV cells than crops if you're interested in efficiency.
Wait - what? The biofuel you get is from the dead plant material, right? Which is constructed using the energy the plant captures via photosynthesis. What other "waste" are you talking about? I think what you're referring to as "waste" is actually the useful product in this case - the plant material that stores the energy captured from the sun, so I don't see a second use from the plant.
True statements. If housing is about location, location, and location, then electric transportation is about batteries, batteries, and batteries.
Well, assuming we run out of coal or oil, liquid fuels would have to some from some bio source, right, else it's all electrical... That's kind of my angle there.
The problem isn't the efficiency of the PV cell, which of course is the sexy part of the equation that researchers just looooove to dig into right away. Oooh - exotic materials! New deposition processes! Publish, publish, publish! Big deal.
Even if I handed you a design for 100% efficient cells tomorrow, you still wouldn't be able to build a commercially successful, cost competitive solar plant outside the Southwest. For example, in New York, sunlight is just too rare (~6 hours per day on average) and too diffuse (324 W/m2 on average) for the efficiency of the PV cell to matter. 100% of a small number is still a small number - an average of 1.9KWh/day/m2 in this case. Therefore, the only way to grow the power output of the plant is to make it larger, and there goes your cost competitiveness, especially after you fight off all the NIMBY lawsuits (to say nothing of your backup plant or storage system for when the sun isn't shining). Now if you could build a PV cell with 300% efficiency, you might be onto something....
Well, if the lecturer told you that, I hope you can get your money back. First Law of Thermodynamics: you can't do better than 100% efficiency. Second Law of Thermodynamics: you can't even get to 100%.
What fraction of the life-cycle cost of a solar plant is in the material for the PV cells? Currently, manufacturing cost is ~$1/watt. Figure we can cut that in half to $.50/W, so a 500 MW plant (modestly sized) would cost $250M for the materials. That's probably less than 10% of the cost of buying the land, getting the permits, building the plant, building the transmission lines, building the energy storage system (for overnight power), and then operating the plant for 20 years. So again, I could hand you free PV cells and it wouldn't really change the basic economics all that much.
