Spain’s struggling solar-power sector has announced it will sue the government over two royal decrees that will reduce tariffs retroactively, claiming they will cause huge losses for the industry.

In a statement, leading trade body ASIF said its 500 members endorsed filing the suit before the Spanish high court and the European Commission. They will allege that royal decrees 156/10 and RD-L 14/10 run against Spanish and European law.

The former prevents solar producers from receiving subsidized tariffs after a project’s 28th year while the latter slashes the entire industry’s subsidized tariffs by 10% and 30% for existing projects until 2014.

Both bills are “retroactive, discriminatory and very damaging” to the sector. They will dent the profits of those companies that invested under the previous Spanish regulatory framework, ASIF argued.

The decrees are part of the newly launched tariff framework that will cut payouts for ground-mounted solar energy projects by 45% this year, killing future investment in the trade, which industry leaders expect will be frozen in the next few years. The law will also see tariffs drop 5% for small rooftop installations and 25% for large ones.

Because of “bad regulation,” the sector has lost 30,000 jobs or 30% of its workforce, ASIF concluded.