With nearly 2,000 cases worldwide, climate change litigation is growing rapidly and has become one of the most powerful tools to enforce or enforce climate law commitments against governments and businesses. In this context, climate science plays a vital role in addressing evidence of causality between anthropological activities and climate change.

Although most private lawsuits target fossil fuel companies, there is a growing number of lawsuits being brought against renewable energy projects because of their harmful effects on the environment and society. The extent to which litigation can weaken or undermine the growth of renewable energy is still unknown, but recent research reveals the high level of carbon footprint of some renewable energy sources (RES) such as hydroelectricity, which will encourage continued climate change litigation.

Although cleaner than fossil fuels, are RES in danger of being banned?

Climate change litigation

Climate change litigation is an umbrella term that encompasses a range of legal proceedings related to climate change. Climate change lawsuits can be brought against states, governments or companies. Advances in climate science, particularly the attribution of greenhouse gas (GHG) emissions to specific emitters, industries, or energy sources, are helping to increase the number of climate lawsuits around the world estimated to more than 2000, if China and Southeast Asia are included (www.litigasia.org ).

Energy demand

The combination of world population growth and industrialization contributes to the increase in global energy demand, which accounts for around 60% of global GHG emissions. In this context, harvesting energy from RES such as hydro, solar, wind is key to achieving the Paris Agreement on Climate Change goal of averting dangerous climate change by limiting global warming to well below 2°C and pursuing efforts to limit it. at 1.5°C.

Hydroelectricity

Hydropower relies on the natural water cycle. It does not need fossil fuel to generate electricity. Moving water (eg river flows, waves, tides) also known as “kinetic energy” spins the blades of a turbine and converts kinetic energy into mechanical energy and then into electricity.

Generally, hydropower generation is considered “climate friendly”. In its sixth assessment report on climate change[1] of 2021, the highly respected Intergovernmental Panel on Climate Change (IPCC) recognizes the importance of hydroelectricity not only to help meet the growing demand for electricity in the world, but also reduce GHG emissions.

The dispatchable power source of hydropower plants, the competitive cost of electricity generation and the overall power density explain why it is the most popular RES and accounts for 16% of global electricity production, second only to the coal and natural gas.

Source: IEA, Hydropower Special Market Report Analysis and forecast to 2030[2]

Electricity generated by hydropower plants increased slightly in 2021 to 4,414 bars of terawatt (TWh), from 4,360 TWh in 2020, while 14 GW of capacity was added in 2021 and 17 GW in 2020. Trends for the coming decades predict a significant expansion of hydroelectricity to reach around 6,000 TWh by 2050, with China and Brazil leading this growth.

Source: US Energy Information Administration, International Energy Outlook 2021[3]

The harmful effects of hydroelectric power plants

From construction to demolition, hydropower plants pose well-documented risks to the environment. These impacts include deforestation, land clearing, habitat loss, water evaporation, manure dumping, siltation, flooding of animal habitat, impeding the free movement of fish, retention of a minimum level of water in the bed during dry seasons, aquatic pollution, population displacement. Not all hydropower plants generate the same level of risk. The severity of environmental impacts mainly depends on the type, age and size of a plant.

The negative effects of hydropower plants on the environment and climate

In some cases, the adverse effects have led to successful lawsuits. For example, in 2020, the Supreme Court of the Slovak Republic ordered the closure of a hydroelectric power station on the basis of “the public interest, which is the protection of the environment, takes precedence over the private commercial interest”[4].

Greenhouse gas effects of hydroelectric plants

Although much attention has been paid to the negative effects of hydropower plants on the environment, recent notice has been taken of the GHG emissions they generate. Although cleaner than fossil fuels for generating electricity, hydroelectric plants can still be carbon intensive. This discovery is surprising because there is no combustion of fuels in the hydroelectric plants in operation.

Publicly and privately funded research, in particular a study conducted by Washington State University in 2016[5] and the 2019 EU-funded HYDROCARB project studied the carbon footprint of hydropower plants. They confirm earlier findings made by Vincent St Louis of the University of Alberta in 2000 that the reservoirs of hydropower plants act as “methane factories”, removing CO2 from the atmosphere and returning it as methane. with a much greater impact on the climate. According to these studies, CH4 is the main GHG produced in dams and results from the bacterial decomposition of organic matter in anoxic water and sediment environments created by the reservoir.

Source: International Rivers, People, Water, Life available at:

https://archive.internationalrivers.org/campaigns/reservoir-emissions

Scherer and Pfister estimate that 10% of all hydroelectric power plants emit the same amount of GHGs per unit of energy as a conventional fossil fuel power plant.

According to the International Energy Agency (IEA) World Energy Outlook 2017 80 kg CO2eq MWh⁻¹ is used as a benchmark carbon intensity for sustainable electricity generation to meet the energy targets of the United Nations 2030 Agenda for Sustainable Development. Based on this, an article published in Nature by Rafael Almeida concludes that over a time horizon of more than 20 years, about 25% of proposed lowland dams in the Amazon may well be more carbon intensive than coal-fired power plants.

Are climate change litigation progressing?

Scientific evidence reveals that GHG emissions from hydropower plants, especially small ones, are significant, but current policies and regulations appear to underestimate these effects. Until tougher legislations are enacted, lawsuits are likely to increase against hydropower plants following the path of climate-related actions brought against fossil fuel companies. Last March, a petition was filed with the US Environmental Protection Agency calling for the development of rules requiring hydroelectric facilities and reservoirs to report their GHG emissions.[6].

The Global Methane Pledge launched at COP 26 pledging to “achieve all possible reductions in the energy sector” is likely to exacerbate the rate of lawsuits against methane emitters, including hydroelectric plants.

While some hope may arise from the 2021 launch of the Hydropower Sustainability Standard that covers GHG emissions, it remains to be seen to what extent it will be implemented and whether countries will start reporting GHG emissions. GHG from dams.

Ultimately, reservoir planning that considers GHG emissions as well as environmental and societal externalities will be key to mitigating the risk of climate change-related lawsuits.

The IEA estimates that 40% of the world’s hydropower plants are at least 40 years old. Solutions to reduce their carbon intensity include upgrading plants with improved designs, reducing nutrient inputs to dams, clearing land vegetation before floods, reducing water evaporation. However, some of these solutions may cause additional environmental risks while addressing some side effects of hydropower plants. For example, the coupling of hydroelectric power plants with floating solar photovoltaic (FPV) installed directly on water bodies makes it possible on the one hand to reduce the rate of water evaporation and GHG emissions and on the other hand FPVs are notorious for their adverse effects on the ecosystem.

Source: Ursual Grunwald et al. Floating Solar Photovoltaic-Hydroelectric Hybrid Systems: Benefits and Overall Assessment of Technical Potential