Solar power & Wind Power for residental use

[MossRoad]

The DC or Ac controversy that resulted in going with Tesla's AC. There was quite a Brohaw between him an Edison I believe.

Yeah, Edison wanted to the market, so he purported AC was dangerous and somewhere in the argument, and elephant was electrocuted to prove his point. In history, Edison comes out looking like a **** and Tesla is the victor.

 

[MossRoad]

Depends on whose Ox has been gored. The Governent for the good of the whole should be able to take over 1/2 of your property, farm it and give the food to needy.

They do that. Its called eminent domain. No roads, power lines or water pipes could be run without it.

 

[k0ua]

Yeah, Edison wanted to the market, so he purported AC was dangerous and somewhere in the argument, and elephant was electrocuted to prove his point. In history, Edison comes out looking like a **** and Tesla is the victor.

 

[bigdeano]

Apparently nobody told these guys this wouldn't work. Just dedicated yesterday.

Morocco unveils massive solar plant - US News

 

[k0ua]

Apparently nobody told these guys this wouldn't work. Just dedicated yesterday.

Morocco unveils massive solar plant - US News

No information on how many megawatts the plant produces in either the writeup or the video. As usual for reporting, no real information. Also no information on the storage technology. I can tell you this much, it might support 650,000 Moroccans, but it darn sure would not support 650,000 Americans or even 650,000 canadians. I would guess it might support 65,000? Just a guess. I would like to have one in my back yard about 1/1000 that size. But I don't have the land for it. With Morocco being closer to the equator, and in the sunny Saraha, it should work pretty well.

 

[buickanddeere]

Actually PV output is proportional to temperature. At first thought a hot dry desert is the ideal location however the heat raises the internal resistance of the semi conductors and reduces output. In ideal conditions the 10KW systems here will go 12KW+ during a bright bitter cold Feburary day around noon.
As for the typical liberal arts student turned reporter. They have lots of emotional impact in story but sparse on the amount of technical info or accuracy.
The system shown is not a PV system. It instead heats a liquid heat transport medium to a boiler. This system has little to no super heater capability for the first stage high pressure turbine. thermal efficiency of this Rankine version of the Carnot Equation.
I wonder what they are using for the condenser's heat sink ? Liquid to air ?
The 2012 estimated price of 1 billion Euro, not US dollars will be closer to 2 billion. Output is 125MW with a peak of possibly 160MW. There is "three hours" of thermal storage but no mention of MW output during those 3hrs.
No mention of the power source from an hour before dusk until two hours after sunrise.
That is a lot of coin for such a small amount of power. Of the four generating stations on the Canadian side of the Niagara River. The 2nd oldest and 2nd smallest of the four, DeCew 2 makes 144mw. The oldest Beck 1 makes 437MW. All four power plants combined can produce 2103MW .
125MW would operate about 25,000 homes with air conditioning during the day. If supper was being cooked, the lights on with laundry and or dishes. 10,000-15,000 homes depending.
Of course count on candles or going to bed at dusk.

 

[k0ua]

As for the typical liberal arts student turned reporter. They have lots of emotional impact in story but sparse on accurate facts

.

Ain't that the truth!. And the more technical the subject is the less information they will report. I have seen whole articles try to explain complex subjects and not a single useful detail is in the whole article. I have lost all faith in journalists of today.

 

[techman]

Actually PV output is proportional to temperature. At first thought a hot dry desert is the ideal location however the heat raises the internal resistance of the semi conductors and reduces output.

To get your facts straight, semiconductors do not have a resistance change with temperature. It is the intrinsic voltage of silicon which for a diode junction is nominally 0.7 volts. Each PV cell will nominally produce 0.7 volts when illuminated. This voltage has a temperature coefficient of -2.2 mV/deg C. Therefore for each deg C colder the output voltage will increase 2.2 mV per cell. So a panel with a nominal output of 35 volts will increase 0.113 volts for each deg C drop. So in the desert at 50 deg C (122 F), a rise of 30 deg C above nominal, the voltage will drop about 9%.

paul

 

[Egon]

To get your facts straight, semiconductors do not have a resistance change with temperature. It is the intrinsic voltage of silicon which for a diode junction is nominally 0.7 volts. Each PV cell will nominally produce 0.7 volts when illuminated. This voltage has a temperature coefficient of -2.2 mV/deg C. Therefore for each deg C colder the output voltage will increase 2.2 mV per cell. So a panel with a nominal output of 35 volts will increase 0.113 volts for each deg C drop. So in the desert at 50 deg C (122 F), a rise of 30 deg C above nominal, the voltage will drop about 9%.

paul

Thanks for the information.

 

[buickanddeere]

To get your facts straight, semiconductors do not have a resistance change with temperature. It is the intrinsic voltage of silicon which for a diode junction is nominally 0.7 volts. Each PV cell will nominally produce 0.7 volts when illuminated. This voltage has a temperature coefficient of -2.2 mV/deg C. Therefore for each deg C colder the output voltage will increase 2.2 mV per cell. So a panel with a nominal output of 35 volts will increase 0.113 volts for each deg C drop. So in the desert at 50 deg C (122 F), a rise of 30 deg C above nominal, the voltage will drop about 9%.

paul

I should have stated and explained that better instead of the over simplification . Semi conductors do free up more electrons at higher temperatures . Hence thermal runaway and "shorting" of over heated transistors, diodes, SCR's, triacs etc.
High temperatures when it is all said and done, reduces the VA capacity of a PV cell.
The point is the cooler the PV's are the better they operate.