Al Gore famously coined the term, "inconvenient truth," to bring attention to man-made or anthropogenic carbon dioxide emissions and other related issues regarding societal functionality, the environment, and sustainability. Meanwhile, solar and wind energy are being touted with almost unbridled, messianic fervor by the main stream media as a sustainability panacea. Clearly, these technologies will play a significant role in a renewable economy. However, in the interest of hastening the ubiquitous and unquestioned deployment of these systems, their own sustainability baggage is often overlooked. These ignored "inconvenient truths" are subordinated in the interest of unquestioned deployment of solar and wind systems. Alarmingly, both of these platforms have major challenges that relate to sustainable land use which will only continue to worsen with the installation of larger, centralized systems.
The Solar and Wind Juggernaut
Solar and wind power are projected to be the dominant energy sources as touted by mainstream media outlets such as Forbes who cite declining costs for both technologies as a major factor.
Forbes' "declining cost revelation" for solar and wind is somewhat pretentious considering that almost any manufactured system experiences hefty cost reductions with increased scale of production.
Others, such as climate zealots, dutifully reaffirm these predictions and grant carte blanche approval for solar and wind in the absence of any critical thinking or value engineering analyses. Neither Forbes nor the zealots bother to understand, acknowledge, articulate, or analyze all the cogent factors impacting economics and overall sustainability.
It seems that vested stakeholders are recklessly pressing for larger and more massive installations in order to continue to drive down economics without analyzing for the potential of unforeseen and damaging consequences.
There is an alternative discourse that definitively shows that large scale solar and wind power are inherently less sustainable and, perhaps, even unsustainable, as system sizes increase. For example, there is tangible evidence that large scale solar farms are capable of causing unwanted and disruptive climate change. This prediction is not surprising because of egregious land requirements. The reality is that solar and wind require anywhere from 10 times to 1,000 times the land area that other fossil fuel or renewable energy technologies require.
Solar and wind energy systems must be players in a renewable economy. But they must be responsible players that are held accountable to the same stringent criteria as other energy sources. That is, they do not warrant a "free pass" simply because they are considered "renewable energy."
Judicious Land Use Is A Vital Component of Sustainability
The United Nations defines sustainable land use as “the use of land resources, including soils, water, animals and plants, for the production of goods to meet changing human needs, while simultaneously ensuring the long-term productive potential of these resources and the maintenance of their environmental functions.”
Consequently, technologies or other human endeavors that displace thousands of acres of ecosystems egregiously compromise the Planet's ability to assimilate carbon dioxide. In the case of solar and wind, the amount of acreage displace can be orders of magnitude higher than other technologies as shown in the graph below.
Figure references: 1 Powerlink article; 2 Strata 2017; 3,4 AD, 45% & 90% conversion, repsectively; 5 NEI Report 2015
The data in the graph above are clear in that solar and wind systems rank at the bottom regarding sustainable land use. Consequently, there is a significant trade-off for using these technologies for large scale, centralized energy production. This information alone suggests that other alternatives merit serious consideration.
Comparison of Solar and RNG/LNG Systems Land Requirements
It is interesting to compare solar with an energy system such as RNG/LNG which has more favorable land use metrics. The graph shows the relative land requirements for solar and RNG/LNG systems for three different energy production scenarios: 10, 25, and 50 MW-Day.
This graph and other information makes interesting points:
- Because of the over 30 fold disparity in land area requirements of the two energy systems (Solar average = 21 and RNG/LNG = 685 from the first figure), the graph shows that for a 10 MW-Day of energy, a solar system will require a little over 100 acres more than an RNG/LNG system.
- With high bioconversion ADs, the disparity in land area requirements of the two energy systems (Solar average = 21 and RNG/LNG = 1,300 from the first figure) climbs to 62 fold. For this case, it means that for a 10 MW-Day of energy, a solar system will require almost 200 acres more than an RNG/LNG system.
Summary
The need to decarbonize the global economy is considerable. Initiatives that reduce GHG emissions, particularly with respect to carbon dioxide production caused by fossil fuel energy sources, are important. However, implementing large scale solar and wind systems that have significant environmental and economic repercussions mandates the use of proven structured project development and implementation protocols that employ FEED methodologies. The FEED effort must also consider other technological alternatives. Other technological alternatives warrant consideration if only to ensure that the chosen solution is thoroughly scrubbed and not simply prejudicially pre-selected.