Solar energy technology is taking so long to advance itself as a result of the skew of Earth's populus toward easier sources of energy.
"Easy energy" is, and will always be dominant as the fuel for the forces of nature. In Physical Science terms (and you guys know it), it takes on many forms of quantitative measurement, but it has no universal standard of measurement. The general understanding of energy in science is still (loosely, but maybe necessarily) that it exists and functions according to its 'observable' kinesis (worked energy) versus its cumulation (as potential). This reality, combined with the general perception of energy as a seemingly boundless resource for our future survival, process and progress, makes us naturally complacent as living beings. It also makes all matter into what it is (as we see it), based on the intrinsically influential properties of energy as a quantity.
In my country (Australia), the recognition of the sluggish progress of solar technology as a viable source of energy is still overweighed by our national hunger for more readily accesible alternatives. Ironically, we label solar energy as an "alternative" process! Of all the habitable continents on the planet, ours is the most drenched with sunlight. We know we have the capacity to utilise such massive quantities of available energy efficiently, but our econo-politico-sociological existence continues to revolve around the current (global) state of standard living. Our primary source of electric power is from burning coal, yet we continually accept (perhaps submit to) the amount of wasted energy (from coal-fired power stations) as part of the process of energy supply. Thousands of kilometres of conductive wire over the continent enable this energy to be distributed to the most remote communities in the country. However, apart from the extra energy loss (mainly via heat) through these wire networks, the end-users themselves are mostly oblivious to where the energy came from (let alone what they did with that energy).
We (in Australia and in many other countries) are aware of our potential, provided we accept change. Change (in terms of energy use) is about willing ourselves to cooperate as an intelligent entity (or bunch thereof....) to accept that we must change from fossil fuels as the best source of energy for our future.
Fossil fuels are finite, wasteful, polluting and non-efficient. Solar energy is (from Earth's current perception) infinite, free, clean and (although open to improved efficiency) positively beneficial.
The question has to be asked.....................
Do any of you really care?