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What is the effect of the potential integration of heat pumps, electric vehicles and photovoltaic systems into distribution networks? Particularly where the grid is already congested, as in the Netherlands? The Netherlands is currently facing serious network capacity problems, at a time when more and more renewable energy projects, particularly solar, are coming on line.

The researchers analysed the effects of these technologies on overloads and nodal voltage variations in different distribution networks across the country and according to season.

Using computer software, they simulated grid conditions in three situations: photovoltaics and electric vehicles alone; or photovoltaics and heat pumps; and finally the combined penetration of photovoltaics, heat pumps and electric vehicles. They set the simulation penetration rates at 50%, 80% and 100%.

Using real data from Dutch distribution network operators, the researchers found that Dutch suburban areas are the most vulnerable to increased penetration of all technologies. In both summer and winter, suburban networks were overloaded by up to 800%. In terms of line overload, the two suburban networks are overloaded from a total penetration rate of 50%, while the heavy suburban networks have lines with an overload of more than 700%.

"The light suburban network sees a voltage drop below 0.9 per unit (pu) even from a penetration ofpenetration of 50% (once), and also once the voltage drops below 0.85 pu at 100% penetration," they said. "Multiple incidents of undervoltage are observed in the heavy suburban network at all three penetrations. They reach up to 0.65 pu, and 0.42 pu at 80% and 100% penetration, respectively."

Line overloading was absent in the light rural network, but was evident in the heavy rural network with a penetration rate of 80%.

Similarly, in the urban networks, there were no cases of undervoltage or overvoltage. In winter, the urban networks showed a maximum transformer overload of 331% and a line overload of 164% at full penetration. In summer, too, at 100% penetration, these figures were 258% and 125% respectively.

"The more frequent use of heat pumps for heating/cooling causes a higher overall impact on the network, but the longer charging periods of electric vehicles cause more lasting violations," said the researchers.

"Higher insulation and improved energy labelling of future buildings are strongly recommended to minimise the impact of future electric heating on the grid," they said.

https://www.pv-magazine.com/2023/09/22/suburban-grids-most-vulnerable-to-high-levels-of-ev-heat-pump-pv/

PV Magazine, 22 September 2023

Editor's note Behind this technical argument lies a fact that will have to be resolved if we want to electrify everything: the current grid is not designed to support the installation of heat pumps and battery recharging in countries with a high urban concentration or a grid close to saturation.

There's no point in promoting one type of product if the "stewardship" doesn't follow. Our world has too much of a tendency to focus on one subject and neglect the context or the consequences.