Coal, Renewables

The top 10 super ideas list from Renewable Energy World North America

By Nancy Spring
Senior Editor

It was hard to decide on a “Top 10” list of ideas from Renewable Energy World Conference and Expo, March 10-12. Keynote speakers, presenters and conference delegates all had a lot to share. If you attended the REW conference, send me your Top 10 list of super ideas for renewables and we’ll compare notes.

1. Hold the natural gas. Conventional compressed air energy storage systems require natural gas to heat the air that turns the turbines. A dual-fluid energy storage system being developed at Boise State University does not, making it more renewables-friendly and not site-specific.

2. Rooftops are real estate, too. The recession has closed lots of doors, but opportunity knocks for those looking for room for solar photovoltaic installations. If that old manufacturing facility is for sale cheap, connected to the grid and built with acres of flat roof, install solar panels and sell the renewable power.

3. Drill smarter. Enhanced geothermal systems (EGS) could take on what Charles Baron, lead on geothermal efforts, calls the baseload challenge, “because the resource is enormous. Geothermal displaces coal directly making EGS a serious climate technology.” But EGS means drilling deep into rock and that’s expensive, so Google’s a big supporter of the “non-contact” drilling process developed by Potter Drilling. Potter says its technology is based on a process known as hydrothermal spallation that starts by applying a high-intensity fluid stream to a rock surface to expand the crystalline grains within the rock.

4. Firm renewable energy supply. At, you can use “a tool that assists utilities in finding a basket of renewable energy resources that will reduce variance.” Now in the beta stage, all the developers want in return is your feedback.

5. Balance the grid and make money, too. Ireland’s 6.5 GW grid is 25 percent wind power and when the wind stops, “we essentially lose half the grid,” said Electricity Supply Board International (ESBI) manager Philip LeGoy. ESBI is looking at six solutions to its grid operating difficulties, including using large-scale hydrogen fuel cells for storage. In one scenario, wind farms situated on small islands off the coast of Ireland would power fuel cells to produce hydrogen. Barges would pick up the hydrogen and transport it to land, where it would be sold. ESBI found this plan more cost-effective than building underwater transmission lines—and might start a new revenue stream for the company, too.

6. Go back to basics: water. Instead of hoping for a breakthrough storage technology, remember one that’s tried and true. “Hydropower is the best battery we have,” said Linda Church-Ciocci, executive director, National Hydropower Association. There’s new interest in pumped hydro storage, with many projects likely to be filed with the Federal Energy Regulatory Commission, she said.

7. “I need to know how much wind is on my land.” Or you might want to know how much power existing wind projects are producing. The National Renewable Energy Laboratory (NREL) has an extensive library of interactive maps on its website.

8. Can’t use the credit? How about cash? The stimulus bill permits investors to receive cash in lieu of credits, so investors don’t have to have taxable income, something that was slowing down investment in renewables even though Congress has extended the tax credits for wind and solar and other technologies. Denise Bode, CEO, American Wind Energy Association (AWEA) and formerly a tax lawyer, said projects are back on track because of the change. “I have never seen this important a change in tax law,” she said. “It’s astonishing.”

9. Don’t count coal out: add solar. Integrating central solar power (CSP) cycles with Rankine cycle coal plants is beneficial in several ways, according to Kelly Beninga, WorleyParsons Group: the cost of electricity is lower, the system is more efficient than a stand-alone CSP and it can go online more quickly.

10. Remember who’s footing the bills. When planning a mega-project like building transmission lines, be sure the consumer is happy with what he gets, said Roberto Denis, senior vice president, energy supply, NV Energy, the host utility for the conference. “Cost is a major concern. We have to be sure we’re not building transmission to nowhere. Consumers have to pay for it and they vote.”