If you are a homeowner in Poland with solar panels, you have probably heard that the old net-metering system is gone. Since 1 April 2022, new prosumers are settled under net-billing. But what does that mean in practice? Under net-metering, you could offset each kilowatt-hour (kWh) you exported against one you imported — a simple one-to-one swap. Under net-billing, the two flows are settled separately: you sell your surplus at a market-linked price and buy what you need at the retail price. The result is that the value of your exported kWh is not equal to the value of the kWh you import. This guide explains exactly how the system works, what your surplus is worth, and what you should check before you sign a contract.
Poland replaced the net-metering system (known as ‘opust’) with net-billing for new prosumers from 1 April 2022. Under the old system, for every kWh you fed into the grid, you could withdraw one kWh later without paying for the energy itself (you still paid distribution fees). It was a simple energy swap. Under net-billing, the settlement is financial, not physical. You sell the surplus energy you feed into the grid, and you buy the energy you consume. The two transactions are separate.
Here is the practical flow:
The key point is that the RCEm price is usually lower than the retail price you pay for electricity. That is because the retail price includes network costs, taxes, and margins. So, for every kWh you export, you do not get a full kWh back — you get a fraction of its value.
RCEm is the average monthly market price of electricity on the Polish power exchange. It is set by the market and published by the Energy Regulatory Office (URE). The exact value changes every month, so there is no fixed rate. As of 2026, the URE website provides the current and historical RCEm rates. You should check the latest figure to understand what your surplus is worth in a given month.
Because RCEm is a wholesale price, it does not include the costs of delivering electricity to your home. That is why it is lower than the retail price. The difference can be significant, so it is important to size your system to maximise self-consumption rather than exporting as much as possible.
| Aspect | Net-metering (old system, for installations before 1 Apr 2022) | Net-billing (new system, for installations after 1 Apr 2022) |
|---|---|---|
| Settlement basis | Physical: 1 kWh exported = 1 kWh imported (energy only) | Financial: exported kWh valued at RCEm, imported kWh at retail price |
| Value of surplus | Full retail value of the energy (but you still paid distribution fees) | Wholesale market price (RCEm), which is lower than retail |
| Billing | Offset in kWh, with surplus carried over | Offset in money, with surplus credited to your account |
| Impact on self-consumption | Less incentive to match generation with consumption | Strong incentive to use as much of your solar power as possible |
| Who is affected | Prosumers who connected before 1 April 2022 (they may stay on net-metering for a transition period) | New prosumers from 1 April 2022 |
As the table shows, the main difference is that net-billing values your surplus at a wholesale price, not the retail price you pay. This means that every kWh you export is worth less than every kWh you import. The gap between RCEm and retail price varies, but it is always positive — the retail price is higher.
The practical consequence is that you should aim to increase self-consumption. Every kWh you use directly from your panels saves you the full retail price. Every kWh you export earns you only the RCEm price. So, if you can shift your electricity use to times when your panels are generating (e.g., running appliances during the day), you will get more value from your system.
For example, if the wholesale RCEm price is roughly half of the retail price you pay, then every kWh you export earns you only about half of what importing a kWh costs. Over a year, that gap adds up. Therefore, it is worth considering a battery to store excess solar power for evening use, rather than exporting it.
Net-billing is implemented by your electricity supplier, and the details can vary. Here are the key points to verify:
Always read your contract carefully and ask your supplier for a clear explanation of how they calculate your settlement.
Given the net-billing rules, here are practical steps:
Remember, the exact numbers depend on your supplier, your consumption profile, and the current market prices. There is no one-size-fits-all answer, but the principles are clear.
For the most accurate and up-to-date information, always refer to the official sources:
These are the authoritative sources for the rules and prices. Your supplier may also provide guidance, but always cross-check with the official data.
Net-billing changes the economics of solar in Poland. Your surplus is not worth as much as it used to be, but solar still makes financial sense if you maximise self-consumption. Understand the RCEm rate, check your supplier’s settlement details, and consider a battery to store your excess power. By doing so, you can get the most value from your investment.
