Debunking common renewable energy myths

Key points:

• Common myths about renewables are outdated and unsupported by evidence. Misinformation is often behind concerns that renewables are inefficient, too intermittent or too damaging to nature. This briefing helps debunk the myths by providing evidence-based facts, including:
  • Renewables are now the cheapest and fastest-growing source of electricity. Solar and wind costs have fallen dramatically since 2010 (by up to 90%), making them more affordable than fossil fuels.
  • Modern energy systems can rely on renewables. Battery storage, diversified supply, and smart grid systems can manage variable solar and wind generation. Local renewable energy generation shields countries from supply shocks in fossil fuel markets, making energy systems more resilient and secure.
  • Wind and solar energy have lower impacts on wildlife, public health and waste compared to fossil fuels. Renewables help mitigate the impacts of climate change on people and the planet.

Renewable energy is fundamental to net zero, but myths still circulate

Renewable energy and energy efficiency are crucial for the transition to sustainable energy. Switching to energy from renewable sources and using energy more efficiently are two of the most fundamental steps on the path to net zero, curbing greenhouse gas emissions and helping to mitigate global warming. 

Renewables are expanding quickly around the world, mainly driven by the rapid deployment of wind and solar photovoltaic (solar PV) generation. In 2000, renewables met around 19% of global electricity demand, a share that increased to nearly 32% by 2024. This is even more impressive when you consider that global demand for electricity more than doubled from just under 15,300 TWh in 2000 to nearly 31,000 TWh in 2024. Wind and solar generation together grew from 31 TWh in 2000 to over 4,600 TWh in 2024. 

Renewables have become the least expensive source of new power generation globally. In 2023, the average cost of generating electricity from a solar PV plant, known as the levelised cost of energy (LCOE),¹Calculated using the levelised cost of energy (LCOE) for solar PV vs. the weighted average LCOE of fossil fuel alternatives. LCOE is the average cost of electricity generation over the lifetime of a power plant, including the costs of building and operation. It allows a comparison of the costs of different technologies, even if they have different fuels, life spans, capacities and financial profiles.was 56% less than the average of fossil fuel-fired alternatives. The LCOE of new onshore wind projects was 67% lower. Since 2000, the rise in renewable power generation worldwide has saved the electricity sector at least USD 409 billion in fuel costs.

Despite their benefits, some common misunderstandings still circulate about renewable energies, mainly around solar and wind, often as a result of misinformation. This briefing helps to debunk them.

Common renewable energy myths

Myth: Renewable energy technologies are expensive

Compared with fossil fuels or nuclear power, many renewable technologies were developed relatively recently. As manufacturing processes and technologies have improved, the cost of most renewable electricity has plummeted and will continue to fall. The most dramatic declines in electricity costs globally between 2010 and 2023 were seen in solar PV (90%), onshore wind (70%), and offshore wind (63%).

The falling cost of building a renewable energy project means that the technologies compare very favourably with fossil fuel options. In 2023, the global average cost of building a new onshore wind project was 67% lower than the cheapest fossil fuel option, while the cost of a solar PV project was 56% lower than the average fossil fuel option. 

The fall in the cost of renewable projects is making them an increasingly attractive investment option. Investment in renewables, and the grid and storage technologies to support them, now outstrips investment in all fossil fuel technologies combined.

Generating electricity from renewables can help people save money. Solar and wind projects have driven down electricity prices in wholesale markets in some countries, especially at times of peak generation, sometimes to below zero. The International Energy Agency (IEA) estimates that consumers in the EU saved around EUR 100 billion between 2021 and 2023 as a result of new solar and wind replacing expensive fossil fuel generation following Russia’s invasion of Ukraine. These savings could have been 15% higher if renewable deployment had increased more quickly.

Both the IEA and the International Monetary Fund (IMF) say that taking early action to transition to a more sustainable energy system will be cheaper for countries in the long run. Delay will mean much more stringent and costly policies will be needed in the future to limit global temperature rise, meaning greater macroeconomic impacts, whereas shifting to renewable energy allows consumers to benefit from lower power prices. 

The rapid decline in costs also helps explain why some renewables technologies are being deployed so quickly. 450 GW of new solar capacity was installed globally in 2024, compared to 350 GW in 2023.²Zero Carbon Analytics estimations based on IEA data.

The amount of wind capacity installed between 2019 and 2023 avoids around 830 million tonnes of CO2 a year, and the solar capacity installed over the same period avoids 1.1 billion tonnes of CO2 a year – more than the annual emissions of Germany and Japan combined.

Myth: Renewables are unreliable and cannot meet power demand

Some renewable technologies, such as solar and wind, have variable output depending on weather conditions, also known as intermittency. Lack of wind or low wind speeds can reduce output from wind turbines and lack of sun can impact solar generation, but reductions or pauses in generation are manageable for power grid operators.

Renewable technologies are becoming more efficient as designs and reliability improve, improving their capacity factor—the ratio of a technology’s actual energy output to its maximum potential. The average capacity factor for solar PV rose from 14% to 16% between 2010 and 2023, while that of onshore wind rose from 27% to 36%.

The capacity factors of other renewable technologies are even more impressive. Concentrated solar power (CSP) has an average capacity factor of 55%, an 83% increase in efficiency since 2010, and for offshore wind it increased from 28% in 2010 to 41% in 2023. The capacity factor of offshore wind is comparable to conventional fossil fuel generation – higher than that of onshore wind thanks to bigger turbines and more sustained winds at sea. The IEA classifies offshore wind as a “variable baseload” technology, meaning that, while output will vary, it can be relied on to contribute to the steady background demand of a power system, known as the baseload. 

As renewable energy capacity grows and more of the grid relies on renewables, projects will increasingly need to be combined with electricity storage technologies as part of an integrated grid. Energy storage stores surplus power when demand is low and generation is high, and releases it at times of peak demand to maintain a consistent power supply. An interconnected power system allows grid operators to draw on other forms of renewable generation or from storage when one technology is producing less. A review of academic studies found that 100% renewable electricity systems backed up with energy storage are both technically and economically feasible.

Batteries are rapidly becoming cheaper and more widely deployed. The cost of lithium-ion battery cells dropped by an impressive 97% over the three decades from 1991, dramatically improving the affordability of both energy storage and electric vehicles. New storage technologies such as Long Duration Energy Storage (LDES), which can store power for anywhere from days to weeks or months, can increase reliability, particularly in isolated power systems with limited interconnectivity. Hybrid systems, with solar, wind, lithium-ion batteries and LDES, lower costs compared to standalone battery or LDES systems.

Sometimes renewable generation is stopped because the networks they are connected to have not been upgraded sufficiently to accept all of their output, rather than from a failure of the renewable source itself. This is a practice known as ‘curtailment’ or ‘constraining off’. In some areas, it is common to see wind turbines not turning and, less obviously, solar PV projects might be non-operational for this reason. The IEA estimates that around 3% of renewable output was curtailed in 2021 in ten markets with high levels of renewables, amounting to around 40 TWh – equivalent to New Zealand’s annual electricity demand.

In reality, all sources of power will be unavailable at some point. Large fossil fuel and nuclear power plants are generally offline around 7–12% of the time due to maintenance, refuelling or unexpected outages. Nuclear plants may be shut down unexpectedly for safety reasons. The Kashiwazaki-Kariwa facility in Japan, the largest nuclear power plant in the world, had to be closed in 2007 after an earthquake, and 46 of France’s 56 nuclear reactors were offline for at least a quarter of the time between 2019 and 2023. Although rare, a problem at a nuclear power station that results in a nuclear accident has long-lasting impacts that reach far beyond interrupting the power supply.

Renewables can actually help make energy systems more secure. The IMF found that Europe’s policies to reduce emissions, including installing renewables, help to ensure a secure power supply and make the system more resilient. Renewables help limit Europe’s reliance on imported energy, diversify its energy imports and reduce vulnerability to energy shocks. A package of measures to lower emissions in line with the EU’s Fit for 55 proposals, which aims to reduce emissions by at least 55% by 2030 from 1990 levels, would improve energy security by nearly 8% over the same period.

Myth: Fossil fuels are more efficient than solar and wind generation

Solar and wind are more efficient than fossil fuels. They produce more usable electricity per unit of energy put in. Fossil-based thermal power plants typically convert only 30–40% of input energy into usable electricity. Renewable sources like solar and wind deliver nearly 100% efficiency, making them two to three times more efficient. It is also worth noting that the input energy for renewable power generation – light energy from the sun and kinetic energy from wind – is free.

When it comes to heating, gas boilers operate at around 85% efficiency, while heat pumps can deliver 300–400% efficiency. In transport, internal combustion engines are just 25–40% efficient, whereas electric vehicles convert 80–90% of energy into motion.

Myth: Renewables create too much waste for disposal 

As with any other energy option, renewable technologies create some waste. The issue is how much waste, and whether it can be reduced by recycling or reusing components. 

To give an idea of scale, global municipal waste is projected to reach approximately 70 billion tonnes by 2050, and coal ash – waste from burning coal, mostly in coal-fired power plants – will reach 45 billion tonnes. By contrast, even in the most pessimistic scenario, end-of-life solar panel waste is expected to total just 160 million tonnes (Figure 1). This means municipal waste and coal ash will outweigh solar PV waste several thousand times.

Figure 1

Renewable energy technologies offer strong potential for recycling. Modern recycling techniques can reclaim up to 95% of a solar panel’s materials by weight, recovering valuable components such as glass and aluminium. Steel used in wind turbines can be recovered and reused, reducing the need to extract new raw materials. Recycled steel produced using renewably powered electric arc furnaces produces 86% less greenhouse gas emissions than traditional steelmaking, and recycled steel consumes significantly less energy and water, and produces less pollution.

Improved standards for solar panels and wind turbines mean both have much longer lifespans today than they did a decade ago. Panels typically last 30 to 35 years and turbines have a lifespan of about 30 years.

Common myths about wind energy

Myth: Wind turbines are too dangerous for wildlife, especially birds and bats

All forms of energy production have environmental impacts, including on wildlife. Renewable technologies present a relatively low risk to wildlife compared to other human activities. Any comparison of risks must take into account the threat that global warming presents to many species, which renewable energy can help mitigate. 

Estimates of the number of birds killed by wind turbines compared to other energy-related causes vary. One study showed that wind power causes fewer bird deaths than fossil fuels when assessed per unit of energy produced. Fossil fuels cause 5.2 avian fatalities per GWh, whereas wind turbines are associated with only 0.3 to 0.4 deaths per GWh.

The extraction of oil and gas disrupts biodiversity during both drilling and production, through, for example, air and groundwater pollution from leaks and spills, light and noise disturbances, and heightened human presence in undeveloped areas. A study in the US found that fracking reduced the number of birds by 15%, whereas wind farms had no significant effect on bird counts.

Nuclear power plants pose other risks to wildlife. Birds are affected by hazardous pollution at uranium mine sites and collisions with draft cooling structures. It has also been proven that bird populations decrease due to radiation after a nuclear disaster.

Figure 2

Looking more broadly, a range of US studies shows that the number of birds killed by wind turbines is a tiny fraction of those killed by cats, buildings, or cars. The American Bird Conservancy estimated in 2021 that approximately 681,000 birds are killed by wind turbines in the US each year. Other estimations indicate a range between 200,000 to 1.2 million for 2022. In comparison, buildings killed an estimated 365 to 988 million birds in the US in 2014, and domestic cats killed between 1.3 billion and 4 billion birds in 2013. 

A review by Sustainability by Numbers provides an indication of the scale of difference between wind turbine-related deaths and some other hazards in the US (Figure 2). 

The impacts of wind development on certain bat species may be more severe. If measures are not taken to reduce fatalities, the North American population of hoary bats could decline by 50% by 2028.

However, many species face much greater risks from global warming. A WWF study of 35 biodiversity-rich places around the world found that 2°C of warming would put a quarter of species at risk of local extinction, rising to 50% at 4.5°C of warming. 

Seabirds in particular are highly threatened – climate change ranks as one of the three major threats to seabirds, alongside invasive species and fishing. Limiting global warming to 1.5°C would benefit 76% of vulnerable bird species, according to the National Audubon Society.

Critically, wildlife protection organisations generally support the development of wind power as a response to the threat of climate change. The American Bird Conservancy recognises that renewables are a “critically important component” in the shift away from fossil fuels, stating that more wind turbines should be deployed but sited to avoid high-risk areas for birds. The UK’s Royal Society for the Protection of Birds (RSPB) has adopted a similar position, stating that climate change is the “greatest long-term threat to nature” and calling for a strategic approach to siting wind projects. 

How wind turbines are located and operated can help reduce their impact on wildlife. Wind turbines can be slowed or stopped at certain times to allow for bird migration or bat activity. Using ultrasound to deter bats is also effective. Bladeless wind turbines are another option – these are cylindrical, flexible structures that capture wind energy by resonating with air flow, with benefits like lower environmental impact and greater safety.

BirdLife International and The American Bird Conservancy both work to ensure that wind energy’s benefits for birds outweigh its impacts. Bat Conservation International also supports renewable energy deployment in a way that minimises impacts on bats.

Myth: Offshore wind farms are too dangerous to marine life

The construction and operation of offshore wind farms can impact marine wildlife by disrupting natural habitats, creating noise and electromagnetic interference, and potentially spreading invasive species. However, these impacts are not unique to the wind industry – they are also caused by offshore oil and gas development. Plus, the oil and gas industry has caused repeated pollution incidents that have degraded habitats and killed wildlife.

Wind farm operations generate relatively low underwater noise. Noise can lead to whales becoming stranded, but this is linked to sudden bursts of noise rather than the continuous operation of turbines. A Danish study found that underwater noise from offshore wind turbines was at least 10–20 decibels lower than that of ships in the same frequency range.

The construction phase can be significantly louder. Marine species such as whales, dolphins, sea turtles and certain fish are particularly vulnerable to the elevated noise levels and tend to move away from the area. But, once established, offshore wind farms can act as artificial reefs that benefit marine life, and some species can come back in larger numbers than before. 

The UN’s Convention on the Conservation of Migratory Species of Wild Animals (CMS) recognises the importance of wind energy in addressing climate change and argues for siting decisions to take into account impacts on migratory species. Different technologies, like bubble curtains, can be used during construction to reduce noise and vibrations. 

The biggest human-caused threats to whales, porpoises and dolphins are being caught as bycatch, entanglement in fishing nets, oil spills, vessel strikes and whaling. 

Myth: Wind turbines create harmful noise pollution

Wind turbines are typically located at least 300 metres away from homes. At that distance, the sound measures around 43 decibels (dB). Sound levels fall below 40 dB beyond 400m from modern wind turbines, lower than the level of noise linked to annoyance in epidemiological studies, and decrease to 38 dB at 500m. By comparison, an air conditioner produces 50-75 dB and background noise in urban areas ranges from 40 to 45 dB. Even in quiet rural areas, background noise is 30 dB.

Although the sound produced by close wind turbines may be perceived as annoying, the Iowa Environmental Council and the Massachusetts Department of Public Health concluded that there is no link between health outcomes and proximity to wind turbines.

Figure 3

Myth: Wind turbines hurt neighbouring communities 

Whilst the announcement of a wind turbine project can impact nearby property prices in the first few years, prices have been shown to recover. A recent US study looked at the prices of houses located within 1.6 kilometres (1 mile) of a commercial turbine. It found that property values declined by 11% following the project’s announcement, but recovered after the project was built. The price difference was insignificant by the five-year mark. The impacts on houses more than 1.6 kilometres away were much smaller or non-existent.

Communities can also make big gains from wind projects. Wind power projects in the US have been shown to increase GDP, boosting the local economy and household incomes. Rural communities benefit the most, as construction and operation can create jobs and diversify work opportunities. Wind projects that are community-owned can bring even greater economic benefits.

Myth: The life cycle emissions of wind turbines are more harmful than burning fossil fuels

Life cycle assessments (LCA) evaluate a product’s environmental impacts throughout its life, from the extraction of raw materials to produce it through to disposal. They allow the impacts of different products to be compared. 

Comparing LCAs shows that renewable electricity generation technologies produce a fraction of the emissions of fossil fuel generation over the product lifecycle (Figure 4). 

Figure 4

Common myths about solar energy

Myth: Solar farms are a waste of agricultural land 

Solar farms are projected to take up a very small proportion of land area. A study projected the land use for solar farms in the EU, India, Japan and South Korea in 2050, when solar energy will account for between 25% and 80% of the electricity mix. It found that solar infrastructure would occupy between 0.5% and 5% of total land area. In comparison, agricultural land accounted for 38.8% of the EU’s land area in 2022.

In the UK, Carbon Brief estimated that existing solar farms (230 km²) and future solar farms (464 km²) combined would use roughly half the land taken up by golf courses. Solar farms make up just under 0.1% of UK land, and government net-zero plans will increase this to less than 0.3%.

In the US, the deployment of solar could lead to between 1.1% to 2.4% of croplands and 0.3% to 0.7% of natural lands being converted for solar PV infrastructure by mid-century. The US Department of Energy calculated that in a 2050 scenario where solar meets 44-45% of electricity demand, solar development would take up around 10.3 million acres (41,683 km²), equivalent to 1.17% of US farmland³Zero Carbon Analytics estimation based on USDA data for 2023 – total farmland of 878,560,000 acres.

Myth: Solar farms are too dangerous for wildlife, especially birds

Like any electricity-generating technology, solar PV will impact the environment and wildlife, although evidence is limited. Birds might collide with PV panels, and there is a theory that water birds could mistake solar farms for water and try to land on them. 

As with wind power, the number of fatalities is small compared to other threats. Mortality estimates vary widely, with studies calculating the annual average avian fatalities from solar to be 2.49 fatalities/MW, 4.5 fatalities/MW, and 9.9 fatalities/MW. 

To address this, some developers are adopting measures such as adding distinctive patterns to panels or choosing places with less bird abundance.

A study by the RSPB and the University of Cambridge found that solar farms in the UK can actually increase the number of bird species, especially if they are managed to encourage wildlife and flowering plants. In the US, the National Audubon Society and other conservation groups work with developers to ensure that climate action, conservation and community engagement go hand in hand on large-scale solar developments.

Myth: Solar panels pollute the environment with toxic materials

According to the Clean Energy Council, solar panels mainly consist of glass (77%), followed by aluminium (10%), polymers (9%), silicon (3%), and copper, silver and tin (<1%). 

The vast majority of solar cells, the part of a solar panel that converts solar energy into electricity, are made using crystalline silicon, as in the Clean Energy Council’s example. They can also contain cadmium telluride, copper indium diselenide and gallium arsenide. These chemicals are enclosed in a solid matrix in the solar cell, insoluble and non-volatile under normal conditions. Because they are stable and enclosed, there is little risk of chemicals escaping during normal use. 

Any pollution of the environment is undesirable, but the impacts of solar panels are minimal compared with the contamination caused by extracting and burning fossil fuels. One study found that soil samples close to solar PV systems showed increased levels of selenium, strontium, lithium, nickel and barium compared to areas further away, but no elements were found in high enough concentrations to endanger local ecosystems. 

Solar module waste is significantly less toxic than coal ash or oil sludge waste from fossil fuel energy generation. The amount of coal ash produced globally in a single month is equivalent to the total projected weight of PV module waste over the next 35 years. Without decarbonising and transitioning to renewable energy sources, the coal ash and oil sludge generated by fossil fuels would be 300–800 times and 2–5 times greater than the waste produced from PV modules, respectively. 

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  Calculated using the levelised cost of energy (LCOE) for solar PV vs. the weighted average LCOE of fossil fuel alternatives. LCOE is the average cost of electricity generation over the lifetime of a power plant, including the costs of building and operation. It allows a comparison of the costs of different technologies, even if they have different fuels, life spans, capacities and financial profiles.
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  Zero Carbon Analytics estimations based on IEA data.
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  Zero Carbon Analytics estimation based on USDA data for 2023 – total farmland of 878,560,000 acres.