by Judith Curry
Will our future be filled with wind turbines, solar farms and transmission lines covering an ever-growing portion of the planet’s surface as energy demand increases? Output of arable land and forests burned to provide electricity?
The amount of land needed for renewable energy is an issue of growing concern but surprisingly little attention. The current global energy system exists on a relatively small area of land (only 0.4% of the land is ice-free), two orders of magnitude smaller than the area used for agriculture.[i] Plans for a fully global renewable energy system would significantly increase the amount of land used for energy production, especially with increasing energy consumption and widespread electrification for heating, transportation and industry.
The land footprint of energy systems displaces natural ecosystems, leading to land degradation and creating trade-offs for food production, urban development, and conservation. In densely populated countries like Japan, Bangladesh, Lebanon, South Korea, India, the Netherlands, Belgium, Bahrain and Israel, there simply isn’t enough land to support much of the energy supply that comes from energy. regenerative. Emerging economies face greater challenges with more dynamic land use ahead of urbanization, industrialization and agriculture.
A recent paper calculated land-based energy use intensity (LUIE) from real data for all major power sources.
Land-use intensity of power generation and future energy landscape
by Jessical Lovering, Marian Swain, Linus Blomqvist, Rebecca Hernandez
[link]
Abstract. The current global energy system has a relatively small land area, accounting for only 0.4% of the land that is ice-free. This pales in comparison to agricultural land uses – 30–38% of land is ice-free – but future low-carbon energy systems transition to more widespread technologies could dramatically change the landscape. globally. The challenge is more acute as global energy consumption is expected to double by 2050 and widespread electrification in transport and industry. However, unlike greenhouse gas emissions, the intensity of energy use on land is rarely studied rigorously. Here, we calculate land-based energy use intensity (LUIE) for real-world locations across all major power sources, integrating data from published literature, a database of data and original data collection. We find a wide range of LUIEs spanning four orders of magnitude, from nuclear at 7.1 ha/TWh/y to specialized biomass at 58,000 ha/TWh/y. By applying these LUIE results to future electricity portfolios of the ten energy scenarios, we conclude that land use could become a significant constraint on the deep decarbonization of electricity system, however, there are still low-efficiency and land-saving land use options.
The calculated LUIE values include both land used for actual energy production as well as land used for fuel sourcing. The study found a wide range of LUIE values spanning 4 orders of magnitude, from the lowest value for nuclear to the highest value for specialized biomass. Regarding LUIE values for natural gas, sources with lower LUIE values are nuclear, geothermal, rooftop solar and residual biomass. Evaluation of LUIE for wind power is complicated because the land area of an individual wind turbine is relatively small; however, the overall area of a wind farm is not just the total land area of the individual turbines, but the area within the perimeter of the wind farm. Wind turbines built on degraded, contaminated, unusable land or on agricultural land will not compete with other uses of that land and will not unduly interfere with ecosystems surface. The problem is that such locations are far from population centers where most of the energy is needed. Offshore wind helps to solve land-use problems (despite competing uses of coastal waters) and also places wind farms closer to coastal population centers.
The land use impacts of carbon capture and storage (CCS) for fossil fuel or biomass power plants are estimated to increase land use by 40% compared to a single house. machine without CCS.
In the US, the onshore wind industry is facing challenges from rural landowners who don’t want wind turbines nearby – they are concerned about noise, reduced property values and destruction of visibility. Over the past eight years, 328 wind farm proposals have been rejected in the US. Renewable energy and transmission projects are being blocked across the country by landowners, consumers and environmental groups.
NIMBY-ism at its best. And the United States is a relatively low population density country, although there are areas, mainly along the coast, with very high population densities.
Biofuels
Misconceptions about carbon accounting, political pressure and short-sighted economics are perpetuating the use of biofuels. Biofuels played an important role in the global food crises of 2008, 2011 and 2022. In 2022, global food insecurity reached a record high. However, about 10% of the world’s grains are being turned into biofuels. Palm and soybean oil from Indonesia and South America are also being burned for fuel and it is estimated that 58% of rapeseed oil in Europe is burned for fuel, despite the high prices of cooking oil. The European Union plans to allocate one-fifth of Europe’s arable land to the production of fuels for bioenergy and also plans to quadruple imports of wood to burn for energy equivalent to about 40% of Canada’s annual timber production (the world’s largest exporter).
The United States uses about 40% of the annual corn production grown on tens of millions of acres of arable land for ethanol production, which accounts for only about 10% of U.S. transportation fuel. It is estimated that the life cycle greenhouse gas emissions of ethanol are no less than that of gasoline and may be greater. Ethanol from corn has exacerbated environmental problems such as soil erosion and poor water quality, contributing to the degradation of farmland, which is more important for food production. If biofuel crops are irrigated, this could exacerbate water supply problems during times of drought. The net effect of biofuels is that emissions from the life cycle could be worse than displaced fossil fuels, worsening food shortages and degraded arable land.
Inference
It is feasible and reasonable to include wind and solar energy in about 30% of the power system, but unless there is hydroelectric backup, energy storage or remote transmission capability, the cost profile for additional wind and solar becomes increasingly detrimental and has increasingly adverse consequences on the reliability and performance of the power system.
Wind farms are a possible solution where land-use and coastal considerations allow. Rooftop solar is a good solution and supports some degree of local autonomy. However, wind and solar are likely to become less competitive as new and better technologies emerge in the coming decades. I don’t see any role for biofuels in the future, where other energy sources are available.
In the coming decades, I suspect that land use will become more important than CO .2 emissions in the identification of electrical energy sources.
