Power is a very complex factor. Let us discuss the capacity to begin with.
Simplest example is of a garden water hose. When there is sufficient pressure and the tap is fully open it would supply water at its maximum, if you open the tap half, supply is reduced and it stops completely when you shut the tap. The same analogy applies to hydel, wind & solar power generation.
Hydel power depends upon water level in the reservoir, wind power upon wind speed and solar power upon intensity of the sunlight (solar radiation) on solar panels. Therefore to say that 100 MW capacity solar plants should produce 100 MW of electricity most of the time is an incorrect assumption.
Power generation from solar panels is based on the annual average solar radiation on PVC panels, total panels area and PVC panels’ quality (efficiency). Additionally since power generated by PVC panels is DC; converting the same to AC can result in up to 20% reduction in output.
Standard criterion to compare power & name plate capacity of different types of power generation is ‘load factor’.
Load factor of more than 90%; that is actual power out per year versus capacity; is only achievable with the large fossil fuel and nuclear plants. For example if a gas based 500 MW power plant has a load factor of 95%, it means that it is producing 500 MW power 95% of the hours of the year.
Typical load factor for small coal based power plants is only about 50%. For land based wind energy & solar energy power installations, load factor on annual basis is about 25 to 30%. Concentrated PVC farms such as QA at Bahawalpur should be able to achieve up to 40% load factor if well set up and good quality photo voltaic cell panels are employed. This means that 100 MW capacity concentrated solar farm would produce full 100 MW during 40% of the hours in a year, in other words at best 100 MW solar plant would produce 40 MW of electricity on annualized basis.
What most people also don’t realize about solar power farms is the land requirement. On the average a 100MW solar farm would require about 100 acres. There is also a degradation of power generation at the rate of about 0.5% each year.
Most important benefit is reduction of CO2 emissions. Power requirement of a normal house if supplied by PVC panels (say about 4KW) would translate into reduction of as much as one tonne of CO2 emission per year versus fossil fuel generated electricity.
Disagreeing with large solar plants doesn’t not imply that countries investing in solar power farms are stupid. Priorities of each country are different. In Pakistan's case cost of energy is very important. For others public safety concerns & environment is of paramount importance. For example Germany shut down all of her nuclear plants and instead started building power plants based on indigenous lignite but with pollution controls. Italy shut down refineries in Genoa & Naples because of environment al concerns. A few years back Canadians ordered Vitol to modernize Come by Chance refinery in Newfoundland. Modernization bill was estimated at $700-million; hence they sold it to Harvest Energy.
I have already mentioned that in my humble opinion best way forward for solar power use is to install the panels on individual houses. Unlike some, I would not dare to doubt any ones’ expertize on power generation, I would only comment that little knowledge is a dangerous thing.
Either you should argue against the OP or in favor!
With your posts its really confusing, weather you r in favor or against the motion!
Now, why you quoted my post? Your basically arguing nothing!
There is nothing which i have not already wrote!
Did i said generation capacity remains same, even when sun stop shinning?
Did i not mentioned about efficiency of solar panels in my first post?
Did i not mentioned of utility of PV in domestic application?
Did i not mentioned Germany investing heavily in solar energy? Did i not mentioned Germany and US spending $BILLIONS in PV energy just across the border!
So... please, read my posts again, point out what is wrong, so i can correct my self, otherwise you are not helping.
Did i challenge any standards?
I know, IEC or NEMA or MEPS or VDE or UL..... describe allowed tolerances, in specifying name plates of electrical components and set guidelines and limits of network parameters, but can you help me list the publication number of IEEE or IEC standard you quote your 95% figure for specifying generation capacity? which is actually not happening in QA solar park and your precise input can really defeat the notion that PV generation should be any different to the conventional generation in specifying capacity.
Since you listed positive side of PV energy, but there are huge down sides too, which are also reason of split among the technocrats of state, but those are highly technical, and cannot be explained here or to a fresh electrical engineer.
In short those are related to the quality of electricity, difficulties in planning of various grid parameters, energy managment... etc. and i have always debated aginst those facts... at least in terms of Pakistan, where electricity is not available, grid is heavily overloaded, consumer already have no right, while state is wasting $ BILLIONS annualy on import of oil and now gs as well.
Now the bloody article writer is finance specialist but is completey over looking the waste of precious forex, which is hard earned by the publuc working in middleast.
Govt. is clearly not acting wise by missing the solar band wagon and not following the road map defined in Pakistan's energy policy 2002, which any one could down load.
I say again... i strongly reject the idea that Pakistan should ban PV energy, as it is against national or economical interest and QA solar park only reflects corruption in Pakistan and ZERO integrity in Chinese business practices.
In the end when we spend money, we should take care that we are not being fooled or cheated by the international conractors.
when it is blessed with flowing rivers and one of the largest fresh water reservoirs in the north. Build the F'in Dams and Hydro-power project. It will generate the cheapest energy in the world. Convert every mother trucking thing in Pakistan to electric power, from cars to trains. , Exports will increase due to lower cost of production, Our Industry will bloom. Foreign investment from Major world companies will fly in due to lower cost of production and higher profits margins. Pakistan will save $15 Billion on oil imports. Spend this $15 billion improving infrastructure, Education or law enforcement. According to multiplier effect $1 spend will cause $4 worth of economic activity. 15 x 4 = $60. Excluding everything else i.e Taxes and foreign investment. My friends we are talking about doubling our GDP in less than a decade. 
