Candidates must be honest about the scale of the climate challenge

Consistent with the findings of the International Panel on Climate Change (IPCC), the climate policy debate has converged on a target of carbon-neutrality by 2050. It has also moved on to how to get there.

While candidates (at least those who accept the human role in rising global temperature) vie for climate cred, they conceal the accurate scale of the carbon-neutrality challenge and set the stage for policy failure. 

This is because their proposals focus on the familiar — electricity and personal transportation — as if they account for the lion’s share of  U.S. carbon emissions. In this narrow view, the rapid decline in the costs of renewable electricity and electric-vehicle batteries puts carbon-neutrality within easy reach. We are already near 10 percent wind and solar power, and electric vehicle sales are finally starting to take off, so we only need a policy push to get us home.

The problem is that electricity and personal transportation together account for less than half of  U.S. carbon emissions; the easy half at that. The remainder is split between other transportation sectors (mainly road freight and aviation) and fuel for heating, cooking, and industry. These are much harder electrify or decarbonize. In transportation, where vehicles must carry their fuel, energy density is king. 

Although some other ground transportation applications can be electrified – for example, by equipping highway truck lanes with overhead wires — many uses demand the energy density that only liquid hydrocarbon fuel can deliver. 

Commercial aircraft cannot fly without it. It is estimated that even in a maximally electrified economy, we will still need as much as 100 billion gallons of renewable liquid hydrocarbon fuel each year (a third of what we use today).

One of the significant advantages of electric vehicles is the high efficiency of converting electrical energy to mechanical work. A well-designed motor can convert well over 90 percent of electrical power to useful work, while an internal combustion engine is hard to convert 40 percent of fuel energy to work with the rest lost as heat. 

However, this leverage disappears when using electricity to generate heat for heating and cooking; it takes about three times the power to displace a unit of heating or cooking fuel than to replace a group of transportation fuel. Furthermore, many industrial processes involve temperatures too high for electric heating and must use a combustion fuel, usually natural gas today. 

Hydrogen is the logical substitute for gas, but renewable hydrogen is made from electricity with considerable energy loss along the way. 

All this battery charging, heating, cooking, and fuel-making adds up to a lot of electricity. Several studies show that with expected rates of economic growth, a carbon-neutral  U.S. economy in 2050 will use three to four times the power we use today.

Recognition that we are building an entirely new, much larger energy system almost from scratch in less than half a century forces us to confront over-arching issues about which we hear next to nothing. First, this unprecedented rate of construction will require a matching rate of capital investment. 

If we expect the private sector to finance much (or all) of it, investors must see a strong business case through the working life of the projects they fund. This means an energy policy that dictates the outcome but not the means (who knows how needs will change or what technology will bring) and is rock solid through 2050 and beyond. Even with stable policy, it is likely that some form of public-private partnership will be necessary. 

Second, to avoid a trade balance catastrophe, a strategy must ensure that the mountains of raw materials and finished technology that go into this project are sourced in the  U.S. wherever feasible with the care that we don’t replace a financial catastrophe with an environmental one.

Third, many social and ecological benefits are intrinsic to effective climate policy. 

The construction and operation of this new energy system will generate millions of medium- and high-skill jobs for decades to come while the elimination of emissions from fossil fuel processing and combustion will dramatically improve urban air quality. 

Recognition of these and many other consequential benefits should reduce the temptation to attach social goals, however laudable, that could stall effective climate legislation altogether.

Most straightforward is often best. Our prospective leaders must tell the whole story, not just the half they like.

Michael Tamor, Ph.D. is an adjunct professor at Arizona State University School for the Future of Innovation in Society and a retired Henry Ford Technical fellow.