Authors: Dag Nummedal.
Reduction of carbon emissions and enhancement of national energy security are desirable goals. Discussions of how to...
Authors: Dag Nummedal.
Reduction of carbon emissions and enhancement of national energy security are desirable goals. Discussions of how to realize these goals, however, generate a lot of heated debate – not all of it illuminating. An accelerated switch to renewable energy may seem like a logical push, yet the vastness of the global energy system is such that even the most optimistic scenarios for development of renewables are not going to bring about a cleaner atmosphere fast enough. Therefore, additional technology changes are needed, and I will argue that many options exist for reducing the emissions from fossil energy and these need to be pursued at all deliberate speed.
First, a switch from coal to natural gas will reduce emissions at all stages of the life cycle: gas emits less CO2 per unit energy than coal during production, transportation and combustion. The "factor of 2" improvement that is often mentioned in the press is only part of story.
Second, fossil energy production takes much less acreage than an equivalent wattage generated by renewable resources. In a world with limited land for food production, minimizing competition from energy production is a good thing. The difference in acreage needs for various energy production systems is vast. For example, biomass takes one million (106) acres to generate the same amount of power (watts) as we can produce from one acre (!) of oil shale, or 10 acres of a major oil field.
Thirdly, research has barely begun to address totally new approaches to decarbonization of the vast volume of unconventional fossil energy resources (oil shale, shale oil, heavy oils, tight gas, shale gas, coal bed methane, gasified coal, hydrates, and "ROZ": the residual oil zone). This research includes incipient work in genetic engineering and catalytic approaches to break the long molecules of these unconventional hydrocarbons and produce only the lightest components: light oils and natural gas. Still, these will also emit CO2 when burned, so the need will continue to exist to generate new products that will reuse emitted carbon (carbon capture and reuse: CCR), or storing some portion of emitted CO2 below ground (carbon capture and sequestration: CCS).