June 20, 2017
To adapt Thomas Pynchon, if the wrong question is asked, the answer doesn’t matter. Today, the world seems to be consciously framing its energy problems in a way that avoids the right questions, and thus true solutions.
Human advancement is intrinsically linked to the development of motorized power driven by fossil fuels. Unfortunately, the resource itself is finite and has serious byproducts, notably carbon dioxide, which may pose an existential threat by worsening climate change. A logical response might be to limit energy consumption and its adverse side effects. However, the modern energy-intensive lifestyle appears sacrosanct. The International Energy Outlook estimates that worldwide energy demand will increase by 48 percent from 2012 to 2040.
Individual transport in a petrol, diesel or electric vehicle now seems to be an inalienable right. Air conditioned comfort is considered essential. The new digital economy consumes about 10 percent of the world’s electricity, which is the equivalent of the amount of energy used to light the planet in 1985. Instead of questioning these insatiable demands, the focus is on finding new sources or switching to renewables. But both those approaches carry risks of their own, and neither answers the right questions.
Exploiting unconventional oils poses significant environmental risks, as illustrated by the 2010 Deepwater Horizon disaster. Fracking and tar-sand oils require large quantities of water for extraction, transport and refining. The process can potentially contaminate groundwater and aquifers, and requires the storing and treating of waste water. Fracking also increases potential emissions of methane, a potent greenhouse gas. Heavy oils and tar sands have a higher proportion of carbon to hydrogen, resulting in higher carbon-dioxide emissions when used.
Renewables have many advantages over these methods. But they also have substantial limitations and drawbacks. Only solar power has the potential to one day replace fossil fuels. Other renewables, such as wind, are too geographically specific or difficult to convert to be economically viable any time soon. All suffer from problems of intermittency, the lack of constant availability, making them unsuitable for base-load energy applications. Unlike traditional power sources, favorable locations for renewable generation are often far from consumers, necessitating realignment of existing energy infrastructure, including the transmission grid.
Renewables also have lower energy density. Coal, depending on quality, provides 50 to 100 percent more energy than the wood it replaced. Oil and gas provide three to six times more energy per weight than coal. In contrast, ethanol, a biofuel, has 30 percent less energy density than gasoline and 12 percent less than diesel fuel. The limited range of electric cars between recharging reflects lower energy density, as a battery has one-sixth the joules-per-kilogram of gasoline. Power density — the rate of energy production per unit of land area — is two or three orders of magnitude higher for fossil-fuel systems than for solar, wind or water production.
In many cases, public policies intended to promote renewables have substantial downsides. Biofuels are often used to meet mandated renewable-fuel targets in developed countries, for instance. But production of the biofuel needed to fill one 25-gallon SUV tank requires the corn sufficient to feed a single person for a year. The grain used to fuel U.S. cars is equivalent to an amount that could feed 400 million people. World ethanol production targets require the diversion of 10 percent of the world’s cereal output from food to fuels, or finding large tracts of extra land that could increase food prices by as much as 40 percent.
For all that, the emission-reduction potential of renewables is often overstated, ignoring their true energy cost. Wind power requires steel towers made from metal smelted by coal-derived coke or arc furnaces, using electricity generated by coal or gas. It also requires turbine blades manufactured from plastics synthesized from crude oils extracted using diesel or diesel-electric motors. New biofuel plantations require additional land clearing, resulting in deforestation. Emissions from altered land use, fertilizers and transportation may well negate the benefit of biofuels entirely.
The real energy debate needs to be framed differently. Perhaps a starting point might be to work out what energy sources are available, calculate their sustainability and then shape energy demand around these constraints. It may mean sacrificing the convenience of private cars for public transit and inefficient large homes in suburbia for smaller apartments located near where we work. It may mean properly pricing the cost of energy, taking into account long-term effects (such as depletion) and by-products (such as carbon emissions).
Unfortunately, a society preoccupied with individuality and convinced that technology can solve all problems will find these choices unpalatable. The emphasis on maintaining and improving living standards means that everybody will continue to prefer facile answers to the wrong questions — generally but especially where energy is concerned.