For 25 years or more the solar-panel folks have promised radical breakthroughs that have never materialized. Instead the output of readily-available, top-of-the-line panels has slowly crept up from around 12% efficiency to around 18% efficiency. This output is measured in direct sunlight with the panel at right angles to the sun. As soon as the angle deviates from a right angle, the output begins to fall off.
But now there really are some radical breakthroughs on the horizon. Panel efficiencies in the laboratory of over 40% have been achieved. New layering techniques using ‘nano’ technology can maintain the efficiency of panels over a wide range of sun angles (this will be terrific for boats). A process for printing ‘nanoparticle ink’ on rolls of substrate, which dramatically reduces costs, has recently gone into full-scale production. This year, various manufacturers plan to open factories with the collective ability to produce solar panels that add up to hundreds of megawatts of rated output. There are even panels that make electricity at night, using infrared light.
So, this may be the year in which the marine market starts seeing a significant improvement in panel output from a given surface area, or a substantial reduction in the cost for a given output. Typically, the latter requires a greater surface area, which is often hard to find on a boat, but in time we should see a combination of higher-powered panels at a lower cost. Looking further into the future, we may well see solar panels built into our hulls, decks and sails.
It is not unreasonable to think that in the not too distant future, at anchor we will be freed from the tyranny of a fossil-fueled engine even on cloudy, windless days. What a fine thought that is!