1 - USDA Hardiness Zone 8 - Southeastern U.S.
2 - 8
3 - If we are talking photovoltaic efficiency, a 3. Although some of the electronic peripheral technology associated with the photovoltaics such as converters, regulators, etc., probably rates an 8 while the storage technology, (batteries, something we are deeply invested in improving here at the University of South Carolina), rates a 2 or less at the moment. If we are talking talking water heaters strictly for hot water consumption in both residential and commercial dwellings ... it probably rates a 6 in its current offering. Basic solar water heaters could be offered at higher levels of efficiency but the technology is cost prohibitive to the average user. Solar collectors, (ambient), used for millennium, are difficult to rate because, argh, nevermind ... I cannot spend another second trying to answer this particular question.
4 - Yes
5 - Both are equally important.
6 - What specific type of Solar Energy System and at what cost? Please include individual design costs, (not R&D related), for a specific application/location, installation costs and maintenance costs. I was fortunate enough to have the knowledge and wherewithal to apply mine own design to my own personal system on my own property. However, most consumers would require a consultant of some sort to design the system that best suits their individual needs based upon various factors such as, location, position and design of dwelling/structure, energy requirements, etc. I am not familiar with current tax laws/incentives with regard to what might be depreciated these days, but the general, common sense, rule of thumb for the average consumer would dictate that the higher the cost the longer the product/system would be expected to operate at a standard level of effeciency - like a good pair of shoes or a great car or truck. Drive-train warranties (engines and transmissions) are offered which are exponentially longer than warranties offered on less exspensive components of the vehicle's overall system. Of course, as with everything, so much depends upon how it is maintained during its lifetime. Segue 3, 2, 1 ...
7 - Minor maintenance, yearly. Major tune ups every five years but based upon the limits of your question maintenance would end in five years or? Service contracts offered in advance that would cover both so that future expenses could be budgeted well in advance. My answer assumes minimum 10 year increments with regard to product lifespan.
8 - Depends upon the initial cost. You cannot dictate the market value of a product based upon what the consumer is willing to pay and over what period of time he is willing to pay for said product. Your entire line of cost/value based questioning violates certain basic capitalistic market principles. Design the product first, then put it out there and see what the market will bear. If it is a good, affordable, product that does what it is advertised to do, then the consumer will pay.
9 - Both are equally important.
10 - ... that they are a necessary evil that are totally out of the consumers' control. That the numerous regulatory commissions designated to oversee costs which are passed-on to consumers are, combined, one of the most corrupt and politically motivated bureaucracies in existence in this country today, from the Federal level right down to the local COOP level.
With regard to your product lifespan question. The average consumer would probably expect two things in order to justify a large investment in alternative energy systems on a residential or small commercial scale.
A - The base system (the system's drive-train if you will), should last, and continue to operate at a high level of efficiency, during the average expected habitation(al)-duration (sic) of the dwelling's inhabitants/owners. In other words, roughly 20 years for residential, probably less for commercial. How long will someone live in the home or occupy the building before it is sold or before they relocate? And what added value will the system bring, or what possible decrease in value might the system cause, at the time of sale?
B - After all costs are calculated, including long term maintenance costs, that the depreciated costs are LESS than current conventional sources. The sheer convenience factor involved would dictate this in a capitalistic society. In other words, most alternative energy systems would be less convenient than being hooked-up and living-off-of the grid system. Therefore, the only justification for converting to independent systems would be a reduction in costs over the investor's (see A above), lifespan of the system and/or the value added during the eventual resale of the property. Of course, potential tax credits and savings realized from such would have to be calculated into this aspect of consumers' expectations when considering the return on their investment.
