Billions are being invested, attempting to develop a fusion reactor. Unlike today's atomic fission reactors, fusion would produce no deadly radioactive waste requiring long-term storage.
Since the 1950s, we have been told that fusion power might be achieved in the next ten years. If we wait long enough, this prediction might even become true, finally. But how long will be long enough? I am not holding my breath!
Fusion power, employing readily available fuels, would indeed have enormous advantages. Unlike today's fission reactors, it wouldn't risk accidents rendering thousands of square miles uninhabitable. It wouldn't put climate-wrecking carbon dioxide into the atmosphere. Unlike local solar energy panels, it could run full blast day and night, summer and winter.
So it might seem reasonable for governments and private investors to pour billions of dollars into developing a fusion reactor. But the case for spending this money is not as strong as one might think.
An old saying holds there is no need to reinvent the wheel. We already have an efficient, well-functioning fusion reactor putting out tremendous amounts of energy. It is only 93 million miles away. We call it the sun.
Historically, the sun has powered virtually all human activities. Sunlight grows the plants that we either consume directly as food or feed to animals which convert it into meat. Sunlight millions of years ago produced the plants which ultimately turned into the coal, oil, and natural gas currently powering modern civilization.
Sunlight drives the climate, evaporating water which, when it falls as rain, can generate electricity as it flows downstream. Sunlight drives the winds which are turned into electricity by wind turbines. And most recently, a rapidly growing number of photovoltaic (PV) panels turn sunlight directly into electricity.
The main disadvantage of solar energy, its local intermittancy from day to night, good to bad weather, and seasonally, can be avoided by wiring up the entire planet into a single grid. The sun, after all, runs 24/7.
Hydro, wind, and PV panels harvest sunlight currently coming in, and thus are "renewable" power. Coal, oil, and gas, on the other hand, harvest power stored up over a long period of time in the past and are therefore nonrenewable. (There may or may not be plenty of these fuels still left, but we probably cannot afford to use them because of the consequences for the climate.)
We already have a fusion reactor, the sun, and can now convert sunlight directly into electricity. We therefore need to compare the money spent trying to develop an earthbound fusion reactor with what it would cost to produce all the electricity we need from sunlight.
Technology for a fusion reactor is speculative, whereas the technology needed to power the planet entirely with solar energy is already well-developed (and getting better and cheaper as we go!).
In other words, we need to consider the "opportunity costs" of fusion research — how much additional solar production facilities we could get by diverting the fusion research money to invest instead in solar energy.
The same question has been raised about money now devoted to researching carbon sequestration and storage — which theoretically could allow us to continue using carbon fuels without fouling our own nest.
A recent commentary by MIT professor Charles Harvey holds that money spent on carbon capture would produce greater reductions in output of carbon dioxide if diverted to building additional solar energy facilities.
And a similar article by Farhad Manjoo explains why money spent building new atomic reactors would also produce a more immediate reduction in carbon dioxide if spent on additional solar energy infrastructure.
Fusion power is indeed great! Our sun being an excellent fusion reactor, we ought to put its power to full use as rapidly as possible — accelerating installation of PV panels and the worldwide grid — and stop wasting money on unneeded research.