Grid congestion areas: what the new BMWE study means for site selection of agrivoltaic projects

5 min read · Updat­ed on 22 Octo­ber 2026

Key points at a glance

• In 2024, only 5 % of sub­sta­tions were capac­i­ty-lim­it­ed for solar (grid con­ges­tion areas); 95 % are avail­able with­out restric­tion.
• The new grid pack­age links redis­patch com­pen­sa­tion to the site: reduced com­pen­sa­tion in grid con­ges­tion areas, capped at 20 % of annu­al gen­er­a­tion and lim­it­ed to 6 years.
• Only 9 % of new solar capac­i­ty in 2025 was locat­ed in con­ges­tion areas, but it caused most of the increase in redis­patch. The prob­lem is high­ly con­cen­trat­ed, not wide­spread.
• Agri­v­olta­ic devel­op­ers such as Ylek­tra ben­e­fit from greater flex­i­bil­i­ty in site selec­tion, which lets them avoid grid con­ges­tion areas in a tar­get­ed way.

Any­one devel­op­ing a ground-mount­ed or agri­v­olta­ic sys­tem today can no longer rely sole­ly on irra­di­a­tion, land avail­abil­i­ty and a grid con­nec­tion com­mit­ment. With the fed­er­al gov­ern­men­t’s grid pack­age, a new vari­able comes to the fore: the sta­tus of the con­nect­ing grid as a capac­i­ty-lim­it­ed grid area, also referred to in polit­i­cal par­lance as a grid con­ges­tion area. On 8 Sep­tem­ber 2026, E‑Bridge Con­sult­ing, on behalf of the Fed­er­al Min­istry for Eco­nom­ic Affairs and Ener­gy (BMWE), pre­sent­ed the data on which this new steer­ing instru­ment is based. The results are direct­ly rel­e­vant for action by solar and agri­v­olta­ic devel­op­ers.

The problem: solar expansion is faster than grid expansion

In some regions, the accel­er­at­ed expan­sion of pho­to­voltaics meets dis­tri­b­u­tion grids that can­not keep pace. The result is grow­ing redis­patch vol­umes and ris­ing sys­tem costs, plus an incen­tive prob­lem: new solar instal­la­tions are some­times built where cur­tail­ment is already above aver­age, there­by wors­en­ing exact­ly the bot­tle­necks that they actu­al­ly help to finance. With­out a steer­ing cor­rec­tive, this effect threat­ened to inten­si­fy as expan­sion pro­gressed.

The regulatory framework: grid package and location-based steering

The cab­i­net deci­sion of 29 July 2026 on the EEG amend­ment and the grid con­nec­tion pack­age address­es exact­ly this prob­lem. The core idea: instal­la­tions that delib­er­ate­ly con­nect to a sub­sta­tion or line sec­tion des­ig­nat­ed as capac­i­ty-lim­it­ed receive reduced com­pen­sa­tion in the event of redis­patch cur­tail­ment, capped for solar at 20 per cent of annu­al gen­er­a­tion and lim­it­ed to six years. Bids will in future be tied to the spe­cif­ic land par­cel, so the grid com­pat­i­bil­i­ty of the site has to be checked before the bid is sub­mit­ted.

A pre­req­ui­site for this loca­tion-based steer­ing is a trans­par­ent, nation­al­ly con­sis­tent des­ig­na­tion of capac­i­ty-lim­it­ed grid areas by the dis­tri­b­u­tion sys­tem oper­a­tors, based main­ly on a cur­tail­ment rate of more than five per cent in the pre­vi­ous year, sep­a­rate­ly for solar and wind, time-lim­it­ed and reg­u­lar­ly reviewed. The E‑Bridge study pro­vides exact­ly this des­ig­na­tion method­ol­o­gy: it was devel­oped in con­sul­ta­tion with the Ger­man Asso­ci­a­tion of Ener­gy and Water Indus­tries (BDEW) and 21 high-volt­age grid oper­a­tors affect­ed by redis­patch, and analy­ses around 3,000 sub­sta­tions based on the Mar­ket Mas­ter Data Reg­is­ter, Open­StreetMap, Netztransparenz.de and weath­er and geo­da­ta, with a focus on 2024, the year with the most reli­able data.

The results: solar expansion remains largely unaffected

For pho­to­voltaics, the study shows that around five per cent of sub­sta­tions were capac­i­ty-lim­it­ed in 2024; 95 per cent of the grid is avail­able to solar instal­la­tions with­out restric­tion. As with oth­er gen­er­a­tion tech­nolo­gies, the lim­i­ta­tion is not a wide­spread phe­nom­e­non but is con­cen­trat­ed in indi­vid­ual grid areas with struc­tural­ly lim­it­ed absorp­tion capac­i­ty, where high solar feed-in already meets recur­ring bot­tle­necks today.

In 2025, the share of capac­i­ty-lim­it­ed grid areas rose fur­ther com­pared with 2024 as a result of new solar capac­i­ty. The spa­tial dis­tri­b­u­tion shows a clear con­cen­tra­tion in regions that already have high solar pen­e­tra­tion; for new projects in exact­ly these areas, the risk of falling under the new loca­tion-based steer­ing there­fore increas­es.

At the same time, the study shows how localised the prob­lem actu­al­ly is: in 2025, only around nine per cent of the new solar capac­i­ty exam­ined was con­nect­ed to capac­i­ty-lim­it­ed sub­sta­tions, but these few sites caused the major­i­ty of the total increase in redis­patch vol­ume (around 72 per cent, solar and wind com­bined). The vast major­i­ty of new solar instal­la­tions there­fore con­tin­ue to be built where they can be inte­grat­ed into the grid with­out sig­nif­i­cant cur­tail­ment. For com­par­i­son: wind ener­gy shows a very sim­i­lar pat­tern, with an even slight­ly low­er share of affect­ed sub­sta­tions. This indi­cates that the steer­ing instru­ment works across tech­nolo­gies on indi­vid­ual hot spots in a tar­get­ed way, instead of struc­tural­ly slow­ing down expan­sion.

What this means for project development

For Ylek­tra, the study con­firms an approach we already fol­low in land acqui­si­tion: grid com­pat­i­bil­i­ty is not a blan­ket region­al char­ac­ter­is­tic but a ques­tion of the spe­cif­ic land par­cel. Since bids will in future be site-spe­cif­ic, an ear­ly check of the con­nect­ing sub­sta­tion deter­mines a pro­jec­t’s cur­tail­ment risk, long before actu­al urban land-use plan­ning begins. We check this fac­tor sys­tem­at­i­cal­ly as part of our site assess­ment, togeth­er with cri­te­ria on devi­a­tions from region­al plan­ning tar­gets and EEG cri­te­ria.

Agri­v­oltaics has a struc­tur­al advan­tage here: dual use of agri­cul­tur­al land often opens up more site alter­na­tives with­in a search area than con­ven­tion­al ground-mount­ed solar, because agri­cul­tur­al use and the grid con­nec­tion point can be con­sid­ered sep­a­rate­ly. Projects can thus be aligned specif­i­cal­ly with non-lim­it­ed grid sec­tions with­out com­pro­mis­ing on agri­cul­tur­al suit­abil­i­ty.

Conclusion

For the first time, the E‑Bridge study pro­vides a reli­able, nation­wide data basis for an instru­ment that works in a tar­get­ed rather than blan­ket way: it address­es a few struc­tur­al hot spots in solar feed-in with­out slow­ing down the over­all expan­sion path of pho­to­voltaics. For devel­op­ers, the com­pet­i­tive advan­tage there­fore shifts fur­ther towards care­ful, ear­ly site assess­ment at land par­cel lev­el, a field in which dili­gent crafts­man­ship in project devel­op­ment trans­lates direct­ly into project eco­nom­ics.

Frequently asked questions (FAQ)

What is a grid con­ges­tion area (capac­i­ty-lim­it­ed grid area)?
A sub­sta­tion or line sec­tion at which more than five per cent of the ener­gy gen­er­at­ed was cur­tailed through redis­patch. The des­ig­na­tion is made trans­par­ent­ly by the dis­tri­b­u­tion sys­tem oper­a­tors and report­ed to the Fed­er­al Net­work Agency.

Who deter­mines which areas are affect­ed?
The dis­tri­b­u­tion sys­tem oper­a­tors des­ig­nate the areas on the basis of objec­tive, trace­able cri­te­ria, tak­ing into account redis­patch calls by both dis­tri­b­u­tion and trans­mis­sion sys­tem oper­a­tors, sep­a­rate­ly for solar and wind tech­nol­o­gy.

From when does the rule apply in prac­tice?
Since the des­ig­na­tion is based on the pre­vi­ous year’s redis­patch data, a des­ig­na­tion can be made at the ear­li­est on the basis of the 2026 redis­patch mea­sures (some of which are still out­stand­ing). The study is intend­ed as a blue­print for the actu­al des­ig­na­tion after the end of 2026.

Does the steer­ing instru­ment slow down the expan­sion of agri­v­oltaics?
Accord­ing to the avail­able data, not struc­tural­ly: 95 per cent of sub­sta­tions are not capac­i­ty-lim­it­ed for solar. What will be deci­sive is an ear­ly, par­cel-spe­cif­ic check of the grid con­nec­tion point in each indi­vid­ual case, which is exact­ly where care­ful project devel­op­ment comes in.

Source: E‑Bridge Con­sult­ing GmbH, “Kapaz­ität­slim­i­tierte Net­zge­bi­ete als Daten­grund­lage für ein Steuerungsin­stru­ment zur Koor­di­na­tion von Netz- und EE-Aus­bau” (capac­i­ty-lim­it­ed grid areas as a data basis for a steer­ing instru­ment to coor­di­nate grid and renew­able expan­sion), on behalf of the Fed­er­al Min­istry for Eco­nom­ic Affairs and Ener­gy, 8 Sep­tem­ber 2026.