On April 10th, in order to ensure the stable operation of the power system, Czech state-owned enterprise - Czech transmission system operator（ Č EPS was forced to shut down its solar power generation capacity of approximately 400MW, accounting for about one-sixth of the country's total photovoltaic power generation capacity.

Spokesperson Hana Kl í mov á said, "After exhausting conventional operating methods to control the power system, Č EPS has decided to initiate a power rationing plan.

Under normal circumstances, grid operators will transmit excess electricity to neighboring countries, but this is not possible on April 10th as all potential importing countries have experienced excess electricity. At present, against the backdrop of high energy prices and strong subsidies, the Czech Republic is seeking to expand its photovoltaic power generation capacity.

The market itself is shifting from residential solar projects to commercial solar projects. We expect C&I to account for 80% of new projects, which is a significant change because in the past three years, our share has been 50/50, "said Radek Orsaga, CEO of local distributor SolSolSolSol." We anticipate that the photovoltaic power generation capacity of the residential segment will be between 150MWp and 200MWp, and the photovoltaic power generation capacity of the commercial segment will be between 600MWp and 800MWp.

This development momentum will be based on a fourfold increase in photovoltaic power generation capacity in 2022, with a total installed capacity of 289MW at that time.

Jan Krcmar, Chairman of the Czech Solar Energy Association (CSA), said: "We expect the new photovoltaic power generation capacity to be between 800MW and 1100MW this year." In addition, he added that after more than a decade of silence in this segmented market, the first batch of ground photovoltaic projects are being launched.

However, he warned that the Czech power grid is not yet ready to adapt to the growing share of renewable energy.

The issue of grid capacity is not a technical issue, but a mathematical problem, "he said.

That is to say, the Czech Republic does not have a transparent system, which makes it difficult for investors to determine whether the grid capacity at a specific location is available. Therefore, they sometimes apply to connect large-scale power grid capacity across the country to determine where they should purchase land. However, this may hinder system operation.

These reservations for large photovoltaic projects have led to some TSOs refusing to connect more small roofs, even though large ground installation systems may not be constructed at all, "Krcmar said, Therefore, it is impossible for some regions to build large-scale self use systems, and transmission system operators can force customers to install much smaller systems or prohibit them from inputting any excess electricity into the grid through fines and deterrence.

In some regions of the country, grid bottlenecks are causing delays in grid connections. Especially, if using the power grid of EG.D, a subsidiary of E.ON, customers have to wait for 8 to 9 months to use photovoltaic power generation. Due to the linkage between rooftop photovoltaic subsidies and grid connections, many customers have to wait for nearly a year to receive payment. This will have a ripple effect on the installation personnel, as they usually only receive payment after the subsidies are in place.

Asymmetric mode

Another disadvantage of the Czech solar industry related to the grid is that its low-voltage grid adopts a unique phase measurement method across Europe. This requires most inverter manufacturers to make firmware changes to ensure that all solar energy consumption passes through one phase, thereby achieving higher self utilization. But not all manufacturers are willing to make such changes, so some Chinese manufacturers have the largest market share.

From 2022 to 2023, the three giants in the Czech photovoltaic market will be GoodWe, Growatt, and Solax. However, due to limited supply of asymmetric inverters and compatible batteries, we have experienced shortages in the market, "said Orsag of SolSolSol. According to reports, the company holds over 30% of the Czech photovoltaic market share.

It is speculated that operating the inverter in this asymmetric mode will shorten the product life to 7 to 8 years, ultimately leading to increased consumer costs.

The official reason for the design of this electricity market is grid stability and can encourage people not to overuse phase. However, the unofficial reason is that transmission system operators can charge up to millions of euros annually for grid connection costs and fees. Of course, there are also power operators who make money from it.

In energy-saving communities built based on the principle of energy sharing, phase measurement methods may also lead to significant imbalances. For example, in an apartment building, this means that one family can obtain cheap solar energy from one phase, while another family can only use expensive electricity from the grid.

In response to lobbying from the solar industry, the Czech Senate has requested the Ministry of Industry and Trade to investigate grid design issues and possible changes to eliminate these restrictions.