If you want the lowest costs per rated power or, in other words, to pay as little as possible for a certain amount of electricity, you should investigate whether thin-film solar panels could in fact be a better choice than monocrystalline or polycrystalline solar panels. This is assuming you have ample space available to use thin-film panels.
Most homeowners don’t really need the best performing solar panels on the market (unless their roof space is very limited). It’s useful to compare solar panels by the price per watt to determine the best value, notwithstanding any space constraints.
Solar panel prices are sometimes listed as cost per watt ($/watt). This is not a sufficient criterion for determining the true value of a solar system.
You shouldn’t judge solar modules on the simple price per watt. Rather you should base your buying decision on quality (reputation of the module manufacturer), warranty, available space, climate, availability of modules, and recommendations from your chosen solar contractor. Price per watt does not address the issue of quality, and it may be wise to remember the old adage “you get what you pay for.”
Also, you should review independent test reports about different solar modules published by solar magazines, not paid advertising. Internet forums, where users can report their personal experiences with specific makes of solar panels, can also be useful. Blogs can also be of interest. Due to the importance of these sources of information for the reader, I’m providing three lists of links to websites (magazines, discussion forums, and blogs). The following online links to reputable solar magazines and journals can provide the reader with objective analyses, ratings, test reports, and other comparisons of photovoltaic modules, inverters, and other PV-related subjects.