Standing on the Cape Charles beach at sunset, you always feel as if you are part of one of the most beautiful places on the planet. As new climate change and sea-level rise scenarios continue to proliferate, coastal communities like Cape Charles have to wonder if someday the western sunset will be seen from a much more western vantage point.
The consensus by many in the scientific community is that human‐induced climate change requires urgent action to reduce carbon emissions. In vogue is the desire to use more renewable energy sources such as wind or solar to combat the proliferation of greenhouse gases and hopefully slow global warming. While renewable energy sources will become an increasing part of the total energy portfolio, they still may not do much to quench the increased global thirst for energy—a demand that is propelling an increase in human-induced climate change. If we are going to continue to meet demand while reducing the production of greenhouse gases, renewable energy sources may not be the golden ticket. President Trump’s cruel and pragmatic, yet accurate assessment of the Paris Agreement is based on a harsh understanding of the sustainability problem, and a rebuke of the last 25 years of political, economic and environmental stasis. Trump, and others understand there is a way forward. It is just not popular, or even acceptable.
The latest report from the Global Wind Energy Council notes that ‘the proliferation of wind energy into the global power market continues at a furious pace, after it was revealed that more than 54 gigawatts of clean renewable wind power were installed across the global market last year’.
The problem with the Global Wind Energy Council report is that it actually indicates that wind energy really isn’t doing all that much at all. Solid, gaseous, and liquid fuels continue to be the dominant energy sources that power the daily industrial grind. Given increasing demand, the reliance on fossil fuel technology will likely increase in the coming years. According to International Energy Agency data, world energy demand has been increasing at about 2 per cent annually for nearly 40 years.
According to the International Energy Agency’s 2016 Key Renewables Trends latest report, barely 1% of the world’s energy comes from wind power. Adding photovoltaic solar does little or nothing to move needle forward. The report notes that wind provided 0.46 per cent of global energy consumption in 2014, and solar and tide combined provided 0.35 per cent.
The scenario gets worse for renewable energy when you take into account that the report focuses on total energy–solid, gaseous, and liquid fuels continue to provide most of the energy used for heat, transport and industrial manufacturing.
A two-megawatt wind turbine can only produce about 0.005 terawatt-hours per year, so it’s going to take a big chunk of the earth’s surface to build enough to even meet just the new demand, not to mention existing demand.
Hidden from view are the adverse environmental impacts of wind turbines on migratory species like birds and bats. Mining rare-earth metals to build the magnets in the turbines has been criticized for the large amounts toxic and radioactive waste the process creates.
Wind turbines are mainly constructed of steel. To hold the weight, they stand on large concrete bases. Of course, steel is made of carbon alloy which comes from mined coal. Coal is also used to generate heat to smelt the ore. The cement used in the bases can contain large amounts of coal ash. Depending on how many turbines are built, it will require a substantial amount of coal (fossil fuels) to do it.
Math does not favor the use of “renewable energy” to solve our energy problems. Wind turbines are already very efficient machines but there is a limit to how much energy you can extract from a moving fluid–the Betz limit. According to Betz’s law, no turbine can capture more than 16/27 (59.3%) of the kinetic energy in wind. The factor 16/27 (0.593) is known as Betz’s coefficient. Practical utility-scale wind turbines achieve at peak 75% to 80% of the Betz limit (www.wind-power-program.com). Wind turbines, in terms of efficiency have almost reached it. In the end, the wind and sun provide a fluctuating stream of low–density energy which will not meet critical transport and industrial-mechanical power needs.
Covering large swaths of the earth’s surface with wind turbines and solar panels is not an aesthetically appealing, or even efficient approach.
Standing on the Cape Charles beach or crossing the Chesapeake Bay Bridge Tunnel, you come to realize that we share this global vista with container ships and semi-tractor trailer trucks (there are 5.6 million tractor trailer trucks registered in the US). This is how we will move products for the conceivable future. The Virginia Port Authority reports that by 2020 they will have the capacity to process one million additional container units annually — a 40 percent increase overall. A large portion of that cargo will be moved by diesel trucks.
|70 percent of all freight transported annually in the U.S. is by trucks, accounting for $671 billion worth of manufactured and retail goods transported by truck in the U.S. alone. Add $295 billion in truck trade with Canada and $195.6 billion in truck trade with Mexico. – Trucking Info|
As diesel powered transport increases, reducing emissions from other, more prominent energy generation processes is one way to check, or even reduce greenhouse gas production levels. As levels of carbon production increase in one area, reducing the amount of carbon produced in other areas is one way to attempt to achieve a balance, or even an overall reduction.
If renewable energy is unable to meet demand, what then?
While arguably not an optimal solution, low emitting fossil fuels like natural gas obtained by horizontal drilling and hydraulic fracturing can fill a temporary gap. Long-term, shifting focus towards engineering smaller redundant, clean, safe nuclear fission, and eventually fusion reactors could provide a means to meet the ever increasing energy needs of the global community in a greener, more efficient way. The International Atomic Energy Agency (IAEA) defines ‘small’ as under 300 MWe, and up to about 700 MWe as ‘medium’, and these types of units have been leveraged by the US Navy for some time.
The high capital cost of large power reactors along with the need to service small electricity grids under about 4 GW (gigawatt electric) is creating a desire to develop smaller nuclear units. Capacity to these smaller units can be added incrementally as required. Economies of scale (cost advantage that arises with increased output) are possible due to the numbers produced. There are also moves to develop independent small units (SMR) for remote areas.
An additional reason for interest in SMRs is that they can more readily be moved into brownfield sites in place of decommissioned coal-fired plants.
As the world grows, and other countries begin to emerge and leverage technology for economic progress, the demand for energy will only increase, as will carbon emissions. Meeting those increased energy needs while reducing greenhouse gasses is our fundamental engineering challenge.
Wind and solar may be part of an overall energy strategy, but they will probably never a play a substantial role in solving the problem of transporting goods, lighting large cities, global manufacturing or powering the progress of emerging nations. A pragmatic approach that guides more resources towards truly sustainable energy production methods such as small nuclear, that are cleaner and can consistently increase output could allow for economic progress and environmental sustainability to peacefully co-exist.