Fact check 5 myths about power grids

Electricity grids are the lifeblood of the energy transition. Without it, wind power from the north cannot reach the industrial centres in the south. By 2045, around 651 billion euros will have to be invested in the expansion and conversion of the electricity grid infrastructure in Germany.¹ But the expansion of the transmission grids often encounters scepticism: health risks, property depreciation, lack of necessity. klimaVest was the first open-ended private investor fund to invest in the transmission system operator Amprion in 2025, thereby enabling access to this critical infrastructure. Reason enough to put the most common biases through a fact check. 

Myth 1: High-voltage lines pose a health hazard 

Electromagnetic fields from high-voltage power lines are one of the most common concerns expressed by residents. The fear: Cancer, Alzheimer’s disease, or other diseases caused by invisible radiation. But what do the facts say?

In Germany, the 26th Federal Immission Control Ordinance (26th BImSchV) protects the population with clear limit values. These are based on international recommendations and have been defined in such a way that they protect against all scientifically proven health risks.² The limit values are based on known action thresholds: Only above these thresholds can electrical and magnetic fields irritate nerve and muscle cells.²

The Federal Office for Radiation Protection (BfS) and the Radiation Protection Commission are constantly reviewing the current state of research.² According to current scientific knowledge, animals and plants are also not damaged by the fields of high-voltage lines.²

Important reminders: The field strength decreases very quickly as the distance to the line increases.³ In addition, electrical installations and devices in the household usually contribute significantly more to personal exposure to low-frequency fields than high-voltage lines in the vicinity.⁴

Nevertheless, the BfS recommends precautionary measures: New power lines should be planned in such a way that they do not lead to an additional burden on the population.⁴ Since 2013, new overvoltage overhead lines from 220 kilovolts have been banned from running over residential buildings.⁵

Myth 2: Electricity grids are degraded and outdated 

Germany actually has one of the most reliable electricity grids in the world. This is proven by the so-called SAIDI (System Average Interruption Duration Index), which measures the average power outage time per year per customer.

In 2024, the SAIDI score was only 12.9 minutes. This means that around 99.998 percent of every household was supplied with electricity.⁶ For comparison: In 2006, this figure was still 21.5 minutes.⁷ In the European comparison, Germany takes the top position.⁶

The high reliability is also evident in the number of short-circuit-like faults, which are particularly relevant for industrial and commercial customers with sensitive systems: With 1.76 faults per 100 kilometres of line length in medium voltage, the 2024 value is in the normal fluctuation range.⁶

The fact that Germany maintains such a high level of security of supply despite the massive expansion of renewable energies refutes the myth of outdated infrastructure. The Federal Network Agency confirms: “The power supply in Germany will continue to be one of the most reliable in Europe and the world in 2024.”⁶

Nevertheless: The energy transition requires massive investments in the modernisation and expansion of networks. Not because the networks are degraded, but because they need to be made fit for the new requirements.

Myth 3: We don't need new grids - only more renewable energy 

This myth overlooks a key challenge of the energy transition: Renewable energy is produced wherever the wind blows and the sun shines. However, electricity is needed wherever industry and the population need it. Without high-performance grids, the energy transition will fail.

Wind power is mainly produced in the north and east of Germany, while the largest demand is in the industrial regions in the south and west. The problem is already apparent today: The costs of dealing with network bottlenecks increased from 1.3 to over three billion euros between 2019 and 2023.¹

A recent study by the Institute for Macroeconomics and Economic Research (IMK) of the Hans-Böckler Foundation estimates that investment needs will amount to a total of 651 billion euros by 2045.¹ Of this, 328 billion euros will be allocated to the transmission networks (high-voltage level) and 323 billion euros to the distribution networks.¹

In order to achieve the climate targets, annual investments would have to be more than doubled from the current 15 billion euros (as of 2023) to around 34 billion euros - an increase of 127 percent.¹ The study concludes: “The decarbonisation of the German economy requires massive expansion and conversion of the electricity grid infrastructure by 2045 in order to cope with the electrification of transport, industry and buildings, among other things.”¹

Without grid expansion, green electricity will remain where it is generated - and cannot replace the coal-fired power plants in the south. 

Myth 4: Underground cables are the better and healthier alternative 

Underground cables are often perceived by the public as the ideal solution: invisible, silent and supposedly free of electromagnetic fields. But the reality is more different.

Underground cables also generate electrical and magnetic fields. While electrical fields are largely shielded by the earth, magnetic fields penetrate the ground almost unhindered.⁸ The Federal Office for Radiation Protection has measured the field strengths: Directly above a 380 kilovolt underground cable, 3.5 microtesla were measured at a height of one metre above the ground. Under a comparable overhead line, it was 4.8 microtesla.⁸

The benefit of underground cables: The magnetic fields decrease significantly faster with increasing distance than with overhead lines.⁸ The limit value of 100 microtesla is complied with in both cases.⁸

However, underground cables also have disadvantages: They are significantly more expensive to manufacture and maintain. Repairs are more complex and time-consuming than overhead lines. They also require cable trenches, which can lead to significant interference with nature and the landscape, depending on the soil conditions.

Since 2013, the 26th BImSchV has stipulated that new high-voltage lines may not run over residential buildings - regardless of whether they are overhead or underground lines.⁵ Both variants are permitted, depending on the local conditions. 

Myth 5: Real estate near high-voltage lines becomes worthless 

The concern about the depreciation of properties near high-voltage lines is understandable. But general statements are too short - the reality is more complex.

Several factors are decisive: the actual distance to the line, visibility from the property, the general market situation and transparency in the sales process. A report from the Scientific Service commissioned by the German Bundestag shows: While individual studies point to impairments, there are no general, scientifically confirmed statements about systematic impairments.⁹

Important for owners: The legal limit values must be complied with at all places of permanent residence.³ According to the state of scientific knowledge, compliance with these limit values does not represent a health risk. An argument that can convince knowledgeable buyers.

The Federal Office for Radiation Protection recommends precautionary measures already during planning: If possible, new routes should not be routed through residential areas, and as the distance increases, the influence on the overall exposure to electromagnetic fields becomes less and less.⁴

A building biology rule of thumb is: One meter distance per kilovolt of voltage. For a 380-kilovolt line, that would be 380 metres.⁹ Although this is not a legal requirement, it is a guideline for planning.