Land requirements · Glossary

Land requirements refers to the spatial area needed by energy installations, grids, storage and other infrastructure. In the power system, this concerns wind turbines, photovoltaic systems on rooftops and open land, the cultivation of energy crops, transmission routes, substations, storage sites, electrolysers, pipelines for heat or hydrogen, and the associated operating areas. This does not mean only square metres on a plan. It also includes setback distances, restrictions on use, visibility, ecological effects and the question of which other uses remain possible on the same land.

Land requirements are usually measured in square metres, hectares or square kilometres. One hectare equals 10,000 square metres, and one square kilometre equals 100 hectares. For comparisons, people often use the area per installed capacity, for example hectares per megawatt, or the land yield, that is, the amount of energy generated per hectare and year, for example in megawatt hours per hectare. Both indicators are useful, but they are only comparable to a limited extent. A high-capacity installation may deliver little electricity if it reaches only a few full-load hours. Another installation may occupy a lot of land and still allow agriculture, biodiversity or a dual structural use. For the assessment, therefore, it is not only the geometric area that matters, but also the type of use and its effect on the energy system.

Sealing, occupation and spatial impact

Land requirements are often equated with land consumption. That is imprecise. In German statistics and policy, land consumption means the new take-up of settlement and transport area. According to the Federal Environment Agency (Umweltbundesamt), it averaged around 50 hectares per day in the years 2021 to 2024. The German Sustainable Development Strategy aims to reduce this increase to less than 30 hectares per day by 2030. The Federal Environment Ministry's integrated environmental programme even specifies 20 hectares per day for 2030. Settlement and transport area also includes unsealed parts such as gardens or green spaces. Land consumption is therefore not the same as sealing.

Three categories help with energy installations. Sealing means that concrete, asphalt, foundations or buildings make the soil permanently impermeable to water. Occupation means that an area is tied up by a use, even if the soil remains open. Spatial impact covers visibility, landscape appearance, noise, shadow flicker, setback distances and restrictions on other planning. Anyone who mixes these categories easily arrives at wrong orders of magnitude.

For wind energy, the distinction is particularly important. What is permanently occupied is mainly the foundation, crane hardstand and access road. An estimate by the Thünen Institute gives about one third of a hectare for the base area and crane hardstand of a modern 4-megawatt turbine. The spatial influence, however, reaches much further, because distances to residential buildings, nature conservation, air traffic, the military, radio links, landscape protection and municipal planning must be taken into account. Anyone who describes the entire setback area as consumed overstates the intervention. Anyone who counts only the foundation underestimates the spatial conflict. Between the turbines, agricultural use generally continues.

For photovoltaics, the case is different. Rooftop systems use areas that are already built on and create hardly any additional land competition. Ground-mounted systems occupy land but for the most part do not seal it. Beneath and between the modules, grassland, extensive grazing or ecological enhancement can develop. According to the Federal Environment Agency, the specific requirement has fallen sharply: in 2006 it was around 4 hectares per megawatt, in 2025 below 1 hectare per megawatt. Installations with a special purpose need more land per megawatt, for example agri-PV or biodiversity-oriented solar parks. In return, agricultural production remains possible on the land or the land fulfils additional ecological functions. Even so, the land remains tied up in planning terms. Not every site is suitable technically, economically or from a nature conservation perspective.

Biomass has a different character. Here the land requirement arises mainly from the cultivation of the energy crops, not from the plant itself. According to the Federal Environment Agency's own calculations, new photovoltaic systems generate around 40 times more electricity per hectare and year than cultivated biomass. Even when storage losses of photovoltaics are taken into account, the gap remains large. The Thünen Institute gives an order of magnitude of 10 to 60 megawatt hours per hectare for bioenergy and about 1,000 megawatt hours per hectare for ground-mounted PV. In addition, there is direct competition with food and feed production, nature conservation, soil quality and the water balance. For residues, slurry or biowaste, this statement applies only to a limited extent, because no additional cultivation area in the same sense is needed for them. Renewable therefore does not automatically mean land-sparing.

Why land matters in the power system

As the share of renewable energy grows, the power system becomes more spatially visible. Coal, gas and nuclear power plants concentrate large capacity at few sites. Wind and solar energy, by contrast, use natural energy flows that are distributed over large areas. This is technically manageable, but it changes planning. Electricity is more often generated where wind, sun and available land come together, and not necessarily where large consumption centres are located.

This results in a close connection with grid expansion. If good wind sites are mainly in one region and large loads in another, the grid needs additional lines, substations and control technology. This infrastructure also needs land. Routes occupy corridors and overhead lines affect the landscape. Underground cables require construction areas and protection strips that can later be used only to a limited extent, for example without deep-rooted woody plants. Substations and converter stations are point-like but visible installations. Anyone who considers only wind farms and solar parks leaves out part of the necessary infrastructure.

Land requirements are also linked to security of supply. How many suitable areas exist determines how quickly and in what spatial distribution generation capacity can be added. If land becomes scarce, is blocked in planning or is designated only slowly, the necessary capacity is not built. The gap must then be closed by other power plants, imports, storage or load shifting. Land is thus not a side condition of the energy transition, but a prerequisite for the expansion path.

Costs also depend on it. A wind turbine at a windy site generates more electricity than the same turbine at a weaker site. If little suitable land is available in planning terms, weaker sites, longer grid connections or more complex permitting procedures must be accepted. For solar energy, land prices, grid connection points, lease models and municipal participation influence profitability. Land requirements thus help determine where installations are built, who receives revenue, which costs are distributed via grid charges or support mechanisms, and where local conflicts arise.

Legal framework in Germany: land targets for onshore wind energy

For onshore wind energy, the land requirement in Germany is set by law. The Wind Energy Land Requirements Act (Windenergieflächenbedarfsgesetz, WindBG) has applied since 1 February 2023 and was last amended in August 2025. It specifies for each federal state a binding share of its land area that is to be designated for wind energy. These shares are called area contribution values (Flächenbeitragswerte). Nationwide, they amount to around 1.4 percent by the end of 2027 and around 2 percent by the end of 2032 of the federal territory. The values are derived from the expansion targets of the Renewable Energy Sources Act (EEG). For the non-city federal states, the targets for 2032 lie between 1.8 and 2.2 percent, and for the city-states of Berlin, Bremen and Hamburg at 0.5 percent. The states can designate areas themselves or pass on sub-targets as binding to regions or municipalities. They may also set higher values or earlier deadlines.

The act clearly shows how precisely a distinction must be made between installation area and planning area. Counted are designated wind energy areas, that is, mainly priority areas, special construction areas and special-use areas. Suitability areas and reserved areas count only toward the 2027 target and only if the spatial plan took effect no later than 1 February 2024. Where the rotor must lie entirely within the designated area, the area is counted only proportionally. For this, a flat strip of 75 metres is deducted from the edge of the area, corresponding to the rotor radius of a standard turbine minus the tower base radius. Plans that took effect after 1 February 2023 and contain height limits do not count. Once a state reaches its area contribution values, wind turbines outside the wind energy areas are assessed under building law only as other projects in the outdoor area (Außenbereich) under Section 35(2) of the Building Code (Baugesetzbuch). Expansion is thereby channelled to the designated areas.

In designated wind energy areas and in acceleration areas modelled on the EU Renewable Energy Directive, the WindBG provides for simplified permitting procedures under certain conditions. This includes in particular the omission of individual environmental and species protection assessments if an environmental assessment has already taken place during designation. In their place come mitigation measures or compensation payments. Areas with enhanced protection status such as Natura 2000 sites, nature reserves and national parks are largely excluded from these facilitations. Land designation thus shifts assessments partly from the individual installation to the planning level.

Typical oversimplifications in the debate

Land only as a loss: This view fits sealed commercial or transport areas better than many energy installations. A ground-mounted PV site can be ecologically worse than species-rich grassland, but better than intensively farmed arable land with heavy fertiliser and pesticide use. A wind turbine can strongly shape the landscape appearance even though farming continues around the installation. The assessment depends on the initial state, construction method, operation, compensation measures and long-term maintenance.
Purely arithmetic land comparisons: If a country's entire electricity generation is presented as a theoretical solar area, an abstract number results. It shows neither grid connection, storage needs, seasons, ownership structures, protected areas nor acceptance. Such calculations illustrate orders of magnitude but do not replace spatial planning. Conversely, blanket statements about unsustainable amounts of land are not very robust if they do not take into account rooftops, brownfield sites, car park canopies, agri-PV or repowering. In repowering, fewer but more powerful turbines replace older ones at the same site.
A single average value for all renewables: Wind energy, photovoltaics and biomass differ greatly in energy yield, spatial impact and competing uses. For the same amount of electricity, cultivated biomass needs many times the land of wind or solar. Despite large setback areas, wind energy directly occupies little land. Photovoltaics on buildings needs practically no additional ground area.
Incomplete comparison with fossil energy: Coal and gas power plants need little land per unit of capacity at the site. The spatial effects, however, also lie in open-cast mines, production areas, ports, pipelines, storage sites and spoil areas. According to the Federal Environment Agency, in 2024 in Germany around 1.2 hectares per day were newly excavated for lignite mining alone. For imported energy sources, part of the intervention occurs outside the country itself. A narrow focus only on the power plant site therefore shifts the system boundary.

Planning, responsibilities and acceptance

Decisions about land are not made on technical grounds alone. In Germany, spatial planning, state and regional planning, municipal urban land-use planning, nature conservation and emissions control law, grid planning and energy-sector expansion targets interlock. For onshore wind energy, the WindBG sets the quantitative framework. The concrete selection of areas is made by the planning authorities of the states, regions or municipalities. For photovoltaics, building planning law, the support conditions of the EEG, grid connection, agricultural use and the municipality's stance play a major role. Areas that exist on paper are therefore not automatically available.

Ownership and local value creation influence acceptance. A site can be suitable in planning terms and still be contested locally if residents feel burdens but see hardly any benefit. Lease payments, municipal participation, citizen energy, trade tax, local electricity models or ecological enhancement do not resolve conflicts, but they change the distribution of benefits and burdens. Land requirements are therefore also a question of governance: who decides on sites, who bears the spatial consequences, who benefits and who can raise objections?

With the electrification of heat, transport and industry, these questions become more important. Heat pumps, electric vehicles and electric industrial processes increase electricity demand but often reduce the need for fossil fuels. The infrastructure shifts: less filling-station logistics, fuel transport and heating oil storage, but more lines, transformers, charging infrastructure, generation plants and storage. Greater land requirements in the power sector can therefore go hand in hand with less land and environmental impact elsewhere. Whether this succeeds depends on planning, site selection and technical integration.

Land requirements are thus not a simple question of quantity. The term requires energy generation, grid connection, competing uses, ecological quality, ownership structures and spatial impact to be considered together. Used precisely, it separates sealing from occupation, the direct installation area from setback and route corridors, and arithmetic potentials from sites actually available. It is precisely these distinctions that make it indispensable for assessing the energy transition.

Sources

Gesetz zur Festlegung von Flächenbedarfen und zur Genehmigungserleichterung für Windenergieanlagen an Land (Windenergieflächenbedarfsgesetz – WindBG) — Bundesministerium der Justiz / Bundesamt für Justiz (gesetze-im-internet.de); 2022-07-20 (zuletzt geändert durch Art. 4 G v. 12.08.2025). §§ 1–4, 6, 6a, 6b und Anlage zu § 3 Abs. 1
Siedlungs- und Verkehrsfläche — Umweltbundesamt; unbekannt. Abschnitte zum Flächenverbrauch und zu den Zielen
Photovoltaik-Freiflächenanlagen — Umweltbundesamt; unbekannt. Abschnitte Flächeninanspruchnahme und Vergleich zur Bioenergie
Photovoltaik auf Agrarflächen – für eine schnelle Energiewende — Thünen-Institut; 2022-11-28. Abschnitt zu Flächenerträgen (nach Suchergebnis-Auszug)
Gesetz zur Erhöhung und Beschleunigung des Ausbaus von Windenergieanlagen an Land (Wind-an-Land-Gesetz) — Bundesministerium für Wohnen, Stadtentwicklung und Bauwesen; unbekannt. Einleitungstext zum Gesetzgebungsverfahren

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Edited by eCMS on 11.11.2026 19:47