Recently, I watched a video of a Zoom call by Solar United Neighbors about their efforts to legalize plug-in PV in the United States. At 20:39, someone from Germany asks a question, or perhaps he is simply inspired by Germany:
“Some German plug-in folks say they don’t need state legislation because they believe they have devices that do not interface with the utility grid.”
The question itself reflects a misunderstanding of both the legal and technical situation in Germany.
From a technical perspective, it is possible to implement zero feed-in using either a digital power meter or a device such as a Shelly 3PM installed in the fuse box. These systems can signal the inverter or battery to produce not more electricity as the household consumes at any given time.
This approach makes sense if you have a battery and want to draw only the amount of energy your house needs when the sun is not shining. However, even in this case, the plug-in PV system remains connected to the grid. That is why it is still subject to the rules governing when and how a device may be connected to the grid.
Before the situation was clarified in the Renewable Energy Act, German utilities attempted to require inspection or even installation by a registered electrician. It remained unclear whether they could take action if a device was not registered and no electrician submitted such documentation.
We, (at the BalkonSolar Verein,) argued that utilities could only disconnect a system, which they had threatened to do, if they could demonstrate that the device caused interference with the grid.
Threating your customer
Other legal threats also appeared to lack substance. For example, utilities suggested reporting consumers for tax evasion if their meter ran backward, since this would reduce electricity tax and VAT payments. However, the potential tax loss would typically be in the low double-digit euro range. Tax authorities or customs agencies, which are responsible for enforcement, generally do not pursue such minor cases.
Another threat involved Section 268 of the criminal code, “forgery of technical records.” However, this provision does not apply to a meter running backward.
More broadly, it creates negative public perception if a utility reports its own customers to the public prosecutor. Even if there were a legal basis, prosecution would likely be declined due to a lack of public interest. The financial impact would be minimal, again in the low double-digit euro range, and it is highly unlikely that a German court would issue a ruling on such a matter.
Is it legal without a technical standard?
Another aspect is whether it is legal to use a device for which no technical standard exists, or one that does not fully comply with an existing standard. Until December 1, 2025, the German standard required a special plug and socket. However, this requirement contradicts the core idea of plug-in PV, since such a product necessitates the involvement of an electrician.
The relevant paragraph reads:
“Energy Industry Act (EnWG), Section 49 – Requirements for Energy Installations; Authorization to Issue Regulations; Authority to Determine Regulations:
(1) Energy installations must be constructed and operated in such a way as to ensure technical safety. Subject to other legal provisions, the generally accepted rules of technology must be observed.
(2) Compliance with the generally accepted rules of technology is presumed if, in the case of installations for the generation, transmission, and distribution of electricity, the technical rules of the German Association for Electrical, Electronic and Information Technologies (VDE) are observed.”
This means that a system is presumed to be safe if it follows VDE standards. However, if a system does not follow those standards or is built outside them, its safety must be demonstrated independently. For example, the manufacturer or importer must be able to prove that the system is safe.
Our lawyers also explained that technical standards and codes are not laws. A private association cannot create standards that carry the same authority as legislation. Therefore, these standards are themselves subject to oversight and review within a state governed by justice and the rule of law (demokratischer Rechtsstaat). This point is particularly important because utilities attempted to use their “technical connection conditions” to impose a registration requirement, referencing these standards as justification.
We never took this issue to court, so it remains unclear how a court would have ruled. However, utilities have since withdrawn their opposition to plug-in PV and are now focusing on other challenges.
The term “generally accepted rules of technology” is itself a legal concept with an open interpretation. Although there are rulings by the German Constitutional Court that address how this term can be understood, the question is whether it refers strictly to formal standards, or whether factors such as availability on the market and ongoing expert discussion also play a role.
It is also important to note that only a small fraction of German electricity consumers have digital meters, let alone smart meters, that would allow utilities to detect feed-in. Germany is still behind on its implementation goals in this area.
Utilities are also reluctant to send personnel to read traditional, non-digital meters. Instead, they prefer to send letters asking consumers to report their electricity usage themselves, and only send someone to verify the reading if there are discrepancies.
Whether the situation is similar in the United States remains an open question. I do not have a clear answer to that. However, it is important to keep in mind that penalties in the US can be significantly more severe than in Germany or Europe.
Legislation: At which level should Americans lobby?
Articles 70 to 74 of the German Constitution regulate the distribution of legislative powers between the federal government and the states.
Article 74, which covers matters under concurrent legislative powers, includes:
“11. the law relating to economic matters (mining, industry, energy, crafts, trades, commerce, banking, stock exchanges, and private insurance), except for the law on shop closing hours, restaurants, amusement arcades, display of persons, trade fairs, exhibitions, and markets;”
“16. prevention of the abuse of economic power.”
These fall under concurrent powers, meaning that the Länder (states) have the authority to legislate only as long as and to the extent that the federal government has not exercised its legislative power by enacting a law.
With the Renewable Energy Act and the Energy Industry Act (EnWG), the federal government has exercised this authority. As a result, the Länder cannot introduce additional legislation in this area.
However, federal legislative power is still constrained by European law and by limits within the German Constitution, such as fundamental rights, due process, and the European Convention on Human Rights.
We were fortunate that legalization occurred during a period when a federal coalition was in power that understood the issue, including people like Sven Giegold of the Green Party. It would likely be much more difficult under today’s political conditions. At the same time, geopolitical events serve as a reminder that renewable energy does not depend on vulnerable supply routes such as the Strait of Hormuz.
Because electricity regulation affects competition, a significant portion of regulatory authority has shifted to the European level. Much of the relevant regulation now originates there, for example the Renewable Energy Directive (EU) 2018/2001.
The European Union’s authority in this area is explicitly based on Article 194 of the Treaty on the Functioning of the European Union, which states:
“Union policy on energy shall aim, in a spirit of solidarity between Member States, to:
(a) ensure the functioning of the energy market;
(b) ensure security of energy supply in the Union;
(c) promote energy efficiency and energy saving and the development of new and renewable forms of energy; and
(d) promote the interconnection of energy networks.”
This also applies to plug-in PV, as the European Union has defined electricity generation units below 800 watts (VA) as not significant for the grid.
Commission Regulation (EU) 2016/631, Article 5, states:
“Determination of significance
- Power-generating modules shall comply with requirements based on the voltage level of their connection point and their maximum capacity according to the categories set out in paragraph 2.
- Power-generating modules within the following categories shall be considered significant:
(a) connection point below 110 kV and maximum capacity of 0.8 kW or more (Type A).”
https://eur-lex.europa.eu/eli/reg/2016/631/oj/eng
This framework is further developed in additional documents. For example:
“C/2026/127 Commission Notice on guidance on innovative technologies and forms of renewable energy deployment (…) In some Member States, the installation of plug-in mini-solar systems is subject to the same permitting procedures and safety requirements as rooftop PV systems. (…) Germany has recently amended its legislation (the Civil Code and the Act on Residential Property and Permanent Residential Rights) to enable tenants and condominium owners to install plug-in mini-solar systems on their balconies. In other Member States, installation or certification by an electrician is required, even though the system only needs to be plugged into a socket.”
The creation of a “single European market,” rather than merely a common market as envisioned in the 1980s, has been a major generational project. As a result, the member states of the European Union are often more tightly integrated economically than the states of the United States. This is especially true for the electricity market, where there is a clear mandate to integrate national markets.
We, at BalkonSolar and similar initiatives, could now consider lobbying the European Commission and Parliament to enable plug-in PV at the European level. If the relevant technical standards that allow plug-in PV are incorporated into the norms by CENELEC, this would be a feasible path.
Can the US Congress legalize plug in pv?
The next question is whether national legislation in the United States could allow plug-in PV.
Organizations such as Solar United Neighbors could seek a legal opinion from American lawyers. One possible argument is based on the Commerce Clause of the United States Constitution (Article I, Section 8, Clause 3), which grants Congress the power “to regulate Commerce (…) among the several States.”
This could potentially be interpreted to allow federal legislation on plug-in PV if, in aggregate, such systems have a substantial effect on interstate commerce, for example through their impact on electricity flows across state lines. This interpretation aligns with the so-called Lopez rule. However, this argument might only become relevant once a significant number of systems are already deployed.
However, even if a legal basis exists, lobbying for such legislation may not be effective, and could even be counterproductive under the current Congress.
As a general observation, once plug-in PV systems become widely available and affordable enough to create a clear economic incentive, they will be difficult to stop. Homeowners can install them in their backyards, and enforcing restrictions would likely require substantial effort, such as proving grid connection or demonstrating interference with the grid.