In the discussion about the cost of electricity from photovoltaic systems, a so-called â€˜grid parityâ€™ is regularly mentioned. It is said to have been reached by now. According to this line of argument, electricity production costs from PV have decreased so far that the power generated is less expensive than the reference from the public grid.
However, the comparison of these costs is incomplete, particularly as various cost components such as levies and taxes are not included in calculation. According to our personal calculations, the use of self-consumption of photovoltaic systems is indirectly supported with up to 17cents / kWh subsidy. A community with 10, 000 households, of which 30% use the option of self-consumption, loses €48,000 in revenue from the concession fee per year. If an additional 10GW of PV system is installed on private homes, then the corresponding shortfall in taxes and levies amount to €240-460 million per year.
In order to increase the share of self-consumption on electricity generated by PV systems, batteries can be used as an additional energy source. Their use is to be subsidised with a support scheme of €50 million. The actual costs of such a program are significantly higher (by up to 14%), as various taxes and levies will not be paid by self-consuming households.
If the current budget is to be maintained at the same level by all electricity consumers, different options exist, including e.g. fixed charges. They would amount to about €250 per household per year in the case of grid fees.