What Is Ground-Mounted Photovoltaics?
In short: Ground-mounted photovoltaics (GMPV) refers to large-scale solar plants built on level land in the outlying area (Außenbereich, the undeveloped open countryside) — typically as a solar park with capacities ranging from a few hundred kWp well into the high MWp range. It is the fastest-growing segment of German PV — under the EEG (Renewable Energy Sources Act) deployment path, roughly half of the 215 GW of PV targeted by 2030 is to be built on open land.
Definition & classification
| Plant type | What |
|---|---|
| Rooftop PV | Modules on existing buildings (homes, commercial premises, logistics halls) |
| Ground-mounted PV (GMPV) | Modules on purpose-built mounting structures on land in the outlying area (meadow, arable field, conversion site) |
| Agri-PV | Special form of GMPV — modules above land that remains in agricultural use (elevated mounting or vertical rows) |
| Floating PV | GMPV on water bodies (gravel-pit lakes, reservoirs) — a niche in Germany |
Typical plant sizes
- Small parks: 0.5–5 MWp, a few hectares, often with municipal or citizen participation.
- Mid-sized parks: 5–50 MWp, 5–50 hectares — the standard size in the EEG auction range.
- Large parks: > 50 MWp, several hundred hectares — usually outside EEG support as a PPA project (see PPA).
The EEG auctions for ground-mounted solar cover plants from 1 MWp up to 50 MWp. Maximum bid per bidder: 100 MWp per auction round (see EEG auction).
Components of a solar park
- Modules — today predominantly crystalline silicon (mono-Si), efficiencies around 21–23 %, in glass-glass construction for long service life.
- Mounting structure — fixed-tilt or single-axis tracking (trackers), driven-pile or screw foundations.
- Inverters — string or central inverters, distributed across the park.
- Medium-voltage grid connection — transfer station, transformer station, cable routes.
- Optional: battery storage — increasingly used for smoothing and for grid services.
Land demand — the rule of thumb
Per installed megawatt-peak, a modern park needs about 0.8–1.2 hectares — depending on the module, row spacing and mounting type. A 20-MWp plant therefore occupies roughly 16–24 hectares. Tracker plants require larger row spacing but gain yield.
Solar-park setup — components, size classes and land demand
Where ground-mounted solar is built
- Privileged areas under § 35 BauGB (Federal Building Code): alongside motorways and double-track railway lines (200-m corridor) — see Permitting.
- Conversion sites: former military, mining or industrial land — privileged in EEG auctions.
- Disadvantaged agricultural land: opened up for the EEG auction through state-level ordinances.
- Arable and grassland via the B-Plan procedure (Bebauungsplan, local development plan): with the consent of the municipality.
- Agri-PV sites: with dual use (agricultural + solar) — see Agri-PV.
Comparison with onshore wind — what the two worlds share
GMPV and wind share the same regulatory and planning space:
- Outlying area (Außenbereich), land-use planning, privilege (§ 35 BauGB).
- EEG auctions with maximum prices.
- Land lease as a revenue source for landowners.
- Grid-connection scarcity (medium- and high-voltage bottlenecks).
- Long lead time for project development.
The differences lie above all in the permitting burden (no BImSchG (Federal Immission Control Act) procedure for GMPV below the thresholds) and in the expert reports (no full avifaunal survey as for wind, but species-protection aspects for insects and ground-nesting birds).