Reducing US greenhouse emissions 50 per cent by 2030: is it likely?

Perhaps changing US public attitudes reflects rising international energy prices for gas, coal and oil in 2021 as economic recovery from the covid-19 disaster around the world is thwarted by constrained supply.

With US natural gas prices alone increasing over the past year (as of October 2021), thus leading to a greater use of coal to generate electricity, the US Energy Information Administration’s Winter 2021 forecast predicted that homes heated with natural gas, fuel oil, and propane will see average price increases of 30-54 per cent respectively, although a modest 6 per cent increase for homes using electricity. 

However, while critics of renewables argue that wind and solar are at the mercy of Mother Nature, others note that the price of electricity is determined by whichever fossil fuel-based power plant has the highest cost and what is happening to the price of natural gas, oil or coal, and that energy prices would be even higher without renewables.

Prior to the covid-19 disaster of 2020, the price of renewables had fallen considerably against other energy sources since 2010.    

Between 2010 and 2019, the price of one megawatt hour (MWh) for solar electricity fell from $378 to $68/MWh with similar price reductions for offshore and onshore wind, while the global price of power from new coal fell from $111 to just $109.

Another source, examining data from 2010 to 2018, indicates that renewables had become the lowest cost option with subsidised wind prices being in the range of $28–$54 per megawatt hour (MWh) and unsubsidized utility-scale solar $32–$42/MWh, thus comparing favourably with nuclear at $118–$192/MWh, coal at $66–$152/MWh and a gas combined cycle at $44–$68/MWh.

Factoring in subsidies, wind prices plunge to $11–$45/MWh and utility-scale solar prices stay relatively stable at $31–$40/MWh.

When considering new generation capacity, looking at the marginal costs to run existing coal or nuclear—$26–$41/MWh and $27–$31/MWh respectively, it is argued that building new renewable energy remains competitive with running existing generation.

Although the US Energy Information Administration expected electricity generated by coal-fired plants to rise by 22 per cent in 2021, the first rise since 2014 after no new coal plants had opened in the US since 2013, it predicted a 5 per cent drop in coal-fired power generation in 2022 to below 2019 levels as natural gas prices eased.

According to the National Renewable Energy Laboratory’s 2019 Annual Technology Baseline, wind technologies will decline at least another 64 per cent by 2050 in its optimistic scenario and at least 44 per cent in its mid-level scenario with solar having similar scenarios of 74 and 47 per cent.

However, the lower cost of greater renewable energy sources must also give adequate attention to the cost of disposing used parts such as used solar panels.

At present, it has been estimated that it costs around $20-30 to recycle one solar panel whereas sending that same panel to a landfill would cost a mere $1-2 with the latter option complicated by panels having hazardous waste because they contain small amounts of heavy metals (including cadmium and lead).

While solar panel recycling legislation may result, hopefully sooner rather than later, there will be a considerable cost from dealing with end-of-life renewables infrastructure that encompasses uninstallation and transportation, with experts also expecting that more than 720,000 tons worth of “gargantuan wind turbine blades will end up in U.S. landfills over the next 20 years while only five percent of electric-vehicle batteries are currently recycled”.

Nevertheless, based on the above evidence and assuming that policies will be implemented to adequately address the disposal of discarded renewable energy materials, I do believe that the US will reduce greenhouse emissions in line with growing world awareness that such measures are needed to temper the adverse impacts of global warming, although it may prove difficult to achieve the Biden Administration’s target of 50 per cent of greenhouse-gas emissions by 2030 compared to 2005 levels.