What exactly does “green energy” mean? Is it the amount of emissions involved? If so, are we talking about emissions connected with energy generation, energy distribution or energy equipment manufacturing?
Or, is it about the amount of land consumed and the degree of disturbance? If so, are we including the land connected with the extraction of the materials needed to make the energy and equipment involved?
These sorts of questions are intricately involved in defining what green energy really is and how green it really is. TreeHugger.com defines it thusly:
“Green energy comes from natural sources such as sunlight, wind, rain, tides, plants, algae and geothermal heat. These energy resources are renewable, meaning they’re naturally replenished.”
Alternative-Energies.net offers a different definition:
“Green energy represents all the clean sources of power that are generated using the natural source of energy available on the planet, which are friendly with environment releasing zero emissions and are also renewable.”
Significantly, the latter site is one offering “news about renewable energy and electric cars.” Therefore, let us think about electric cars for a moment. Are they an example of green energy?
Well, it depends on several factors, the first of which involves the question of how the electricity is made. It doesn’t grow on trees, after all; it can come from any number of sources. Some 23.4% of that electricity is generated by coal, in fact, according to Energy Information Administration data for 2019. Is a coal car green?
A natural-gas car (it accounts for 38.4% of the electricity used by electric cars) would be a whole lot greener than a coal car, of course, but it would still involve some emissions. The two fuel sources, taken together, represent 61.8% of all electricity. Therefore, a typical electric car is, for the most part, a fossil-fuel vehicle. Zero emissions fuel sources (nuclear, hydro, solar and other renewables) account for just 37.2% of electricity.
But what does zero emissions mean? Nuclear power requires power plants that use an incredible amount of concrete, about 190,000 cubic meters for a 1,000-megawatt power plant. Concrete production accounts for as much as 4-8% of all CO2 produced by man, and just supplying the concrete to build a nuclear plant of this size would produce nearly 50,000 tons of CO2. And, these calculations do not include the energy required to get the concrete to a site. Nuclear energy isn’t zero-emission at all. Rather, it is emissions front-ended.
Likewise, electric cars require batteries made from lithium, which is typically mined somewhere else in the world using vast amounts of carbon-producing energy that must be extracted, processed, shipped to battery manufacturing sites, used in manufacturing and then shipped in the form of batteries to electric-vehicle manufacturing sites. Mark Mills of the Manhattan Institute tells us, “A single electric-car battery weighs about 1,000 pounds. Fabricating one requires digging up, moving and processing more than 500,000 pounds of raw materials somewhere on the planet.” That’s anything but zero emissions.
Rare earth minerals are also used to produce solar panels and wind turbines, along with lots more concrete and steel in the latter case. Is anyone calculating those emissions? They are very real. Once again, consider what Mark Mills has to say: “Building one wind turbine requires 900 tons of steel, 2,500 tons of concrete and 45 tons of plastic.”
There is, in other words, a lot more going on with green energy that isn’t necessarily as green as green-energy advocates would have us believe. Electric cars, solar panels and wind turbines result in lots of emissions, and even hydro involves massive land disturbance and stupendous amounts of concrete that yield emissions.
Natural gas involves emissions, too, but a lot less than coal. Because it enjoys high energy density and the shale revolution has made it spectacularly affordable, it is able to have an enormous green effect. Consider these two powerful facts from the Energy Information Administration:
- U.S. electric power sector emissions have fallen 33% from their peak in 2007 because less electricity has been generated from coal and more electricity has been generated from natural gas (which emits less CO2 when combusted) and non-carbon sources. U.S. total energy-related CO2 emissions have fallen 15% since their 2007 peak.
- Changes in the composition of electricity generation and improvements in energy efficiency have led to a decrease in the total carbon intensity of electricity, which has fallen from 619 metric tons per megawatt-hour (mt/MWh) in 2005 to 408 mt/MWh in 2019.
Even more important are the other emissions that have been reduced due to shale gas’s high energy density combined with affordability. A few years ago, I researched what happened when a small power plant in Hunlock Creek, Pennsylvania, converted from coal to gas, and here is what I found using data from the Pennsylvania Department of Environmental Protection:
- The 44 MW coal-fired power plant was retooled as 125 MW capacity natural-gas-fired facility, from producing power for up to 9,750 homes with coal to as many as 27,075 homes with natural gas.
- Along the way, carbon monoxide emissions, linked with increased risk of heart disease, decreased by 66.4% through conversion to natural gas.
- Volatile organic compounds (VOCs), which contribute to asthma and COPD, dropped some 72.1%.
- Particulate matter under 10 microns (PM<10), which gets in the lungs and can cause acute and chronic bronchitis, declined by 92.8%.
- Nitrogen oxides, which create smog and exacerbate responses to allergens, fell by an incredible 95.7%.
- Sulfur oxides, which may be the worst of the lot and a major contributor to emphysema, all but disappeared, being down literally 99.9%.
Those are some pretty astounding greening numbers. Our fractivist friends will be quick to say we ought to also account for methane emissions, of course. EPA data regarding onshore U.S. oil and natural gas production, though, indicates they fell 24% from 2011 to 2017. Meanwhile, oil and natural gas production jumped 65% and 19%, respectively, according to data from the U.S. Environmental Protection Agency and the Energy Information Administration.
Moreover, biofuels, considered green energy by most advocates, generate an estimated 11 million tons of methane emissions, according to the International Energy Agency, or about 8.2% of all energy-related methane emissions, so there is no free ride. Every source of energy involves emissions somewhere along the line. It’s just that gas is the big, green gorilla of green energy when you get right down to what is achieving the most reductions.
About the author: Tom Shepstone is the owner of Shepstone Management Company Inc., a planning and research consulting firm located in northeastern Pennsylvania. He has advised many counties in both New York state and Pennsylvania, as well as other states, on economic development strategies, especially as they relate to rural and agricultural areas. He is also the publisher of NaturalGasNOW.org; a blog focused on the same objective.
