Not true at all. The grid can only take so much intermittent power before it starts causing major issues. 15% is about the maximum. As you approach this limit the problems caused by DG becomes greater and requires much more management.
This has nothing to do with killing green power but making green power producers pay the same costs any other independent power producer would be required to pay. Realistically solar power customers should be compensated at the utility's avoided cost rate, not at the retail rate.
This argument may have some merit when directed at genuine co-producers, those who put in solar for profit, but as related to homeowner solar electric, this is a smoke and mirrors argument by Big Power to kill green power to preserve their profit margins, to maintain demand on their systems, and in most areas of the US to preserve their public monopoly. Homeowners, with irrational exceptions aside, will not put in more solar than they use, and likely will install much less capacity than they use. Their use of solar electric has the same effect as moderate to ultra conservation, i.e., reduces demand for Big Power electricity. They will not put in more solar electric than they use because the cost is very high, much higher than buying from Big Power. As DBoon states
For those who would offer criticism that solar PV is too heavily subsidized, I would offer back that those who are purchasing solar PV systems are assuming a far higher personal cost for their electricity while providing a clean power benefit to others who are not making those personal investments. In essence, these solar PV pioneers are making a personal investment of 50% of the cost of clean power so that others don't have to make as large an investment.
Example - A 5kW solar PV system that generates 6000 kWh of electricity a year for 20 years that has an installed cost (net with subsidies) of $3/watt and $5000 of maintenance and replacements over that time period (probably a pretty reasonable average) averages out to 17 cents/kWh - more than would be paid for bulk power from a utility (separate from the flat-rate monthly fees). For me, the premium would be about 7 cents/kWh over a bulk power utility purchase.
The same is true for me. My annual use (2012-13) is about 12,000 kwh, and my estimated annual production is less than 8,000 kwh. And I have put in a substantial system, 6.5 kwh, in a ground mount array about 250 feet from my house. My system is considerably more expensive than a roof mount, and I did it not to co-produce, but to "do the right thing" and reduce greenhouse gas emissions and other pollutants caused by my use of electricity. The estimated out of pocket cost payback time is very substantial, even after tax credits, and it is likely I won't even live long enough to see that payback time expire.
The limited periods I will produce more than I use will barely begin to offset use by other homeowners on the street on which I live. One or two of my neighbors using central air will consume more than my excess in the summer, and a couple of 1500 watt space heaters will consume more than my excess in winter, if I even have any excess in winter. There is no DG management problem.
Also, except perhaps in limited areas of the US, most homeowners cannot take advantage of any solar electric due to poor solar siting of their homes, shade from trees and other structures, poor roof designs, and lack of other space to install solar. And of those who physically could take advantage of solar, most cannot afford solar or are not motivated to install solar. Reiterating DBoon's comment:
those who are purchasing solar PV systems are assuming a far higher personal cost for their electricity while providing a clean power benefit to others who are not making those personal investments. In essence, these solar PV pioneers are making a personal investment of 50% of the cost of clean power so that others don't have to make as large an investment.
... makes it very good public policy to encourage homeowner solar electric for those willing and able to install it. Homeowner solar electric will always be a very small portion of total US electric production, although solar electric on a commercial scale, on a co-producer scale, will be increasing rapidly. Some of Big Power already are heavily invested in megawatt solar facilities, and this will continue.
Big Power's position with regard to homeowner solar electric is only about preserving the profits they make from small scale users, the homeowner. Homeowners and small users in general pay a higher rate than larger consumers, and then they are penalized both as they try to conserve, i.e., do the right thing, and as they install solar to reduce their carbon footprint.
