Solar-powered flight between Japan and Hawaii merits notice and praise. Most critical is demonstration of battery technology enabling the Solar Impulse 2 aircraft to store enough useful energy to fly at night yet remain light enough to fly at all. Equally admirable is the adventure. Pilot Andre Borshberg, one of two airmen taking turns in the cramped cockpit as the aircraft attempts to fly around the world, set a duration record for nonstop solo flight with the nearly 118-hr leg, which ended July 3, from Nagoya to Kapolei.
The success testifies to human ingenuity and zest for exploration. It demonstrates advancement of solar-energy technology. It will represent a disservice, however, if claims about its meaning for energy policy get out of hand, as they probably will.
Solar flight?
Energy policy too often begins with fantasy and ends in failure. To think that people will, within any meaningful time horizon, fly aboard aircraft propelled by solar energy is to fall into this trap. Someday, maybe, they will. Someday, maybe, people will sprout wings and fly by themselves. Policy-making should work within definable systems, not open-ended dreams.
For now, solar energy's best prospect is the generation of electrical power at stationary facilities. Even in this realm, the challenge is great. Except under unique conditions, power from the sun remains uneconomic. The technology is developing rapidly. Costs are declining. Efficiencies are rising. Batteries are improving in performance and becoming lighter. Still, solar energy costs too much in comparison with conventional alternatives. If this were not so, the governmental mandates and subsidies that support it would be scandalous. Furthermore, no program of mandates and subsidies can make the sun shine continuously.
Solar energy's competitive difficulties in stationary power generation multiply in mobile applications, especially those needing to counter gravity. The Solar Impulse 2, centerpiece of a $100-million project, required 5 days to carry one uncomfortable person and no baggage a distance covered by normal airliners, with their hundreds of somewhat less-cramped passengers and belongings, in 7-8 hr. For obvious reasons of physics, convenience, and scale, overcoming such comparative disadvantages is not in prospect.
Pointing out real-word drawbacks attached to elevated hope for carbon-free energy always elicits scorn from the hopeful. Alas, it has to be done. Unreasonably elevated hope wields too much influence over energy policy these days. It steers policy toward excessive expenditure on too little useful energy.
The central mistake is trying to force exotic energy forms such as solar and wind into use as replacements for, rather than supplements to, conventional energy with powerful advantages of form. Conventional energy from hydrocarbons is cheaper than solar and wind, largely unaffected by weather, and mobile. Hydrocarbon energy has undeniable disadvantages, mainly emissions of greenhouse gases and air pollutants. Policy-making errs, however, when it bases decisions solely on these drawbacks without acknowledging the economic reasons coal, oil, and natural gas dominate energy markets. This myopia drives political thinking about energy these days.
Faddish snub
To the extent it succeeds in influencing official decisions, prejudice against the production and use of hydrocarbon energy is especially costly now. Technical advance expanding supplies of oil and natural gas and lowering their costs is as impressive as the innovation making fuel-free flight tenuously possible in a slow-moving aircraft barely able to seat one. Compared to solar, oil and gas innovation promises vastly more practical energy at much less cost. And development of resources made prospective by technology expands wealth, incomes, and jobs. Several layers of cost thus result from policies that discourage the production and use of economic energy in favor of energy forms requiring subsidization. To ignore them, as policy-making too often does in a faddish snub of hydrocarbons, is irresponsible.
Inspiring as it is, the journey of Solar Impulse 2 offers little of practical use to the formulation of energy policy. Here's hoping the rest of the mission goes safely-and policy-makers confine their responses to its real achievements.
