PORTLAND, Ore. (CN) - Oregon's legalization of marijuana this summer has caused seven neighborhood-wide blackouts, as indoor growers have turned up the sunlamps, a Portland-area utility company said.
It became legal to possess and grow marijuana in Oregon on July 1, and in October, stores began selling pot to adults. People can grow up to four marijuana plants per residence.
Pacific Power, a subsidiary of PacifiCorp, said indoor marijuana grow operations have caused seven power outages since pot became legal in July.
In one case, around 200 customers in Northeast Portland lost power after a transformer blew. Each blackout costs about $5,000 for damage to equipment, and the costs must be passed on to customers, a spokesman said.
Pacific Power's director of safety Roger Blank compared a small indoor grow operation to "hooking up 29 refrigerators that run 24/7."
Constantly running high-watt bulbs and ventilation systems needed to grow marijuana indoors can overtax local electric grids and cause neighborhood blackouts. The company said such operations need a dedicated circuit for the high-intensity, ultraviolet lamps.
Another Portland area utility said it has to replace around 400 transformers a year, and around 40 of them are caused by marijuana grow operations.
"It's common to see 1,000-watt bulbs in a marijuana grow," Portland General Electric spokesman Steve Corson told The Oregonian newspaper. "Maybe you don't need a whole bank of those."
Sale of marijuana is still in its infancy in Oregon. Medical marijuana dispensaries can sell small amounts of pot to adults, but full retail sales will not go into effect until 2016.
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