The Swedish Radiation Safety Authority (Strålsäkerhetsmyndigheten - SSM) has recommended that the operators of four reactors that will shut earlier than planned - Oskarshamn 1&2 and Ringhals 1&2 - should pay higher waste fees to ensure the waste fund is sufficient.
In a letter to the government, SSM said decisions by OKG and Ringhals to close the units early has "affected the financing of future nuclear decommissioning".
Vattenfall - owner of a 70.4% stake in the Ringhals plant - announced earlier this year that it intended to bring forward the closure of the two units to 2018-2020 instead of 2025 as previously planned, because of declining profitability and increased costs. In October it confirmed that Ringhals 2 is to be decommissioned in 2019 and Ringhals 1 in 2020.
OKG announced in October that Oskarshamn 1 would close between 2017 and 2019 and while Oskarshamn 2 would not be restarted and will be decommissioned.
Annika Åström, head of SSM's financial control unit, said: "Changes in the operating times that the licensees have decided represent significant changes in the assumptions that formed the basis for the government's decision on fees for 2015-2017." SSM proposes that the fee paid by OKG should increased from 4.1 öre (0.48 US cents) to 6.7 öre per kWh of nuclear electricity generated. The fee paid by Ringhals should be increased from 4.2 öre to 5.5 öre per kWh.
SSM said the revised figures were based on calculating the "remaining financing requirement" over the future expected electricity production. The contribution rate is usually decided by the government every three years after SSM assesses the amount nuclear generators should pay.
In December 2014, the government backed SSM's recommendation for an almost doubling of the fees paid by utilities into the waste fund for 2015-2017. SSM bases its assessment partly on estimates from the Swedish spent fuel management company Svensk Karnbranslehantering AB (SKB).