Challenging Conventional Wisdom on Renewable Energy's Limits
In making the case for a rapid conversion away from heavily polluting energy sources like coal and nuclear power to cleaner generation, renewable energy advocates often confront the argument that their scheme is impossible due to the intermittent nature of sun and wind.
But a groundbreaking study
out of North Carolina challenges that conventional wisdom: It suggests
that backup generation requirements would be modest for a system based
largely on solar and wind power, combined with efficiency,
hydroelectric power, and other renewable sources like landfill gas.
though the wind does not blow nor the sun shine all the time, careful
management, readily available storage and other renewable sources can
produce nearly all the electricity North Carolinians consume," said
author John Blackburn, professor emeritus of economics and former
chancellor at Duke University in Durham, N.C.. He's also the author of
the books "The Renewable Energy Alternative" and "Solar in Florida."
The study was published last week by the Maryland-based Institute for Energy and Environmental Research,
whose executive director, Arjun Makhijani, called it landmark research.
"North Carolina utilities and regulators and those in other states
should take this template, refine it, and make a renewable electricity
future a reality," he said.
Blackburn used hourly North Carolina
wind and solar data for a total of 123 days in the sample months of
January, April, July and October, with samples taken at three wind and
three solar sites across the state. Solar and wind power generation
were then scaled up to represent 80% -- 40% each -- of average utility
loads for the sample months, with the rest coming from the existing
hydroelectric system (8%) and assumed biomass co-generation (12%).
study figured in projected energy efficiency by assuming an annual
utility load of 90 billion kilowatt-hours, slightly less than the
current 125 billion kWh load, and by calculating average hourly loads
from Duke Energy's 2006 load profile with modifications to show some
reduction in summer and winter peaks due to more efficient buildings.
It also assumed increased storage capacity from a smarter electrical
In the end, with those conditions met, Blackburn
calculated that the required auxiliary generation from conventional
power plants to fill in the gaps would amount to only 6% of the annual
total generation required to meet demand in North Carolina.
goes to the heart of the argument by power companies that have long
dismissed solar and wind as future technologies," said Jim Warren,
executive director of the N.C. Waste Awareness and Reduction Network, a Durham, N.C.-based nonprofit that provided research assistance to Blackburn.
The study was released just days after a new poll
from Elon University in Elon, N.C. found overwhelming public support in
North Carolina for developing the state's renewable energy capacity.
Nearly 80% of the poll's respondents said they favor new wind energy
facilities in the mountains or on the coast, while more than 83% favor
construction of solar facilities.