Renewable energy projects are putting parts of Cornwall’s electricity grid under severe strain, according to the region’s power firm.
Western Power Distribution (WPD) said that without expensive investment the grid would struggle to cope with taking any more power.
And developers could be asked to pick up “a large proportion of these costs”.
Renewables advisor Regen SW warned charges, totalling up to £4m, may bring renewable energy schemes to a “halt”.
New renewable energy projects in the South West rose from 936 in 2009/10 to 47,423 in 2011/12, said Regen SW.