Fuel cell developer Ceres Power may have to wind down or sell off the business, which would effectively end its latest CHP efficient boiler project.
Shares in the company, based in West Sussex, England, dived 76% after it told the London stock exchange the news.
Ceres has been hit by a series of delays on the launch of its combined heat and power (CHP) energy efficient boiler as a result of technical issues with a product designed for homes in Britain and further afield.
The company has been in talks with potential lenders but in a statement it said "despite extensive efforts it has been unsuccessful in securing sufficient funding for the business going forward".
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