|The Bahamas Investor Magazine
June 23, 2009
June 23, 2009
After dot-coms and financial derivatives, many expect green technology to furnish the next global stock market bubble, driven not only by economic and environmental necessity but also by the enthusiasm of the new US administration. For Chris Huskilson, though, president and CEO of the Nova Scotia-based Emera Inc energy and services company, despite the enthusiasm this is no sector for “dreamers.”
Last year Emera bought a 25 per cent stake in Grand Bahama Power Company and intends, says Huskilson, to put half a billion dollars into the region in the next two to three years. “Whether a large part of that is into renewable energy or not we don’t know yet … if the opportunity arises to invest several hundred million—why not?”
But none of that money will be going into the hands of those who cannot back up their claims. Although alternative energy is still a relatively new and small-scale industry, it has already winnowed out those “who have great ideas but can’t deliver. Funds now go to companies that can execute their plans, and move things forward.”
Not that it’s always easy to know which way is forward. Emera came to Grand Bahama with a number of different projects, which include testing wind-speed and constancy to investigate the suitability of a wind farm, and looking into the possibility of capping a landfill site so that methane created naturally by the breakdown of waste could be used to generate electricity.
There is also a more ambitious and technologically adventurous plan to make use of ocean currents. By November of 2009, Emera will be testing a 10m diameter turbine in the waters of Nova Scotia’s Bay of Fundy. With a rotor that can spin clockwise and anti-clockwise—so it will be driven by both incoming and outgoing tides—the turbine should provide 1mW of electricity. The company wants to find out if the same technology could be used in The Bahamas to generate power directly from the Gulf Stream.
“The beauty of it is that the energy you get is completely predictable,” says Huskilson, “unlike solar or wind, where if the sun doesn’t shine or the wind doesn’t blow, you have nothing. But we need a current of four to five knots to drive a turbine, and really don’t know yet if or where we can deploy them. It’s all about finding the right solution for the right area. If this technology doesn’t work, there’ll be another that will.”
Ocean thermal energy
The government-owned Bahamas Electricity Corporation (BEC), which supplies 85 per cent of the islands’ consumers, invited proposals for alternative energy projects in spring of 2008. The 13 schemes shortlisted in January this year were an eclectic mix that included solar, wind, waste-to-energy and OTEC (ocean thermal energy conversion).
Of the available technologies, OTEC, proposed by the Hawaii-based OCEES International, Inc, is perhaps the one that comes closest to “dreamer” status. It uses the temperature difference between the warm water at the ocean’s surface and the cold water at greater depth to drive a heat engine.
In the most efficient arrangement, a mixture of ammonia and water (which has a very low boiling point) is piped through an evaporator which has warm surface water in it. The mixture turns to steam which is used to drive a turbine, before being re-condensed by exposure to cold water pumped up from the ocean depths, and then fed through the system again.
Although OTEC has been researched off Hawaii since 1979 it has, in the words of one senior BEC engineer, “little international penetration as yet.” Nevertheless it is understood to have powerful support within the Inter-American Development Bank (IADB) as an ideal energy solution for tropical island nations. IADB has allocated two technical cooperation grants worth about $1.5 million to The Bahamas to help incorporate alternative energy.
While not wishing to prejudice the selection process, one source at BEC points out that geography “will most likely determine the success of the bids. If you want to build a solar farm, you need space, and cheap land. And if you want to put up a wind farm, you need isolation—those turbines are big and loud. No one’s ever going to stick them up off Lyford Cay [exclusive Nassau community].”
Bahamas Renewable Energy Corporation (BREC), in partnership with Emera and the Canadian-based Schneider Power Inc, is proposing a combination of wind and solar farms on New Providence, the Abacos and Eleuthera. “Although the sun regime is very good in The Bahamas, solar energy is expensive so we have to include a wind component to be cost effective,” says Thomas Schneider, vice chairman and president of Schneider Power.
The two systems would also act as back-up for each other. The Abacos, for example, average seven hours of sunlight a day, while also experiencing trade winds that blow, says Schneider, “well above the 25 per cent of the time that you need for wind power. The turbines turn even in a gentle breeze—it’s not about wind speed, but wind constancy, and the trade winds make The Bahamas very predictable.”
A kilowatt-hour (kWh) of wind-generated electricity costs about 8-9¢, less than a third the current cost of solar power. The electricity is obviously generated without any need for fuel, but these figures are based on capital investment and maintenance over a theoretical 20-year amortization. “Although,” says Schneider, “if well looked-after the equipment will last 30 years. But often you’ll replace units every ten years anyway, because of improvements in technology.”
Solar power uses sunlight falling on a sheet of photovoltaic material—usually a sandwich of semiconductors—to liberate electrons from their atoms so they can flow through the substance, creating an electric current. It can be used on a domestic scale, and Schneider estimates that “80 per cent of the homes in The Bahamas would find that solar panels on the roof would make economic sense.”
In fact the National Energy Policy Committee, a public-private sector body set up by the government in 2008, wants to make solar water heaters mandatory for all new buildings, and suggests that government incentives could see 30 per cent of Bahamian households with solar heating installed within 10 years.
What BREC and its partners are proposing, however, is of an altogether different order of magnitude: a $60 million investment in vast photovoltaic and wind farms that would generate 24mW for BEC’s local grids. For this they require a lot of land.
“It takes 50 acres of solar panels to get the same electricity as one wind turbine with a footprint of 48 square metres,” says Schneider. “That’s enough to power roughly 300 homes.” This is why some at BEC question the idea of a solar farm on New Providence.
From rags to riches
Although there is little cheap land, there is an enormous amount of garbage, making waste-to-energy a more plausible option. The most environmentally friendly procedure is gasification, in which waste is not burned, but is subjected to heat to turn it into a gas. The Plasco Energy Group, a private Canadian company and one of six short listed firms to propose a waste-to-energy scheme, uses high-temperature plasma torches to refine the gas before it is converted and used to drive electricity-generating engines.
There are no air emissions in the conversion of waste into gas and emissions coming from the creation of electricity are lower than the strictest world standards.
Plasco claims to get 1.2MWh of electricity from every tonne of waste converted, with by-products including 300 litres of potable quality water, 150kg of inert, construction-quality aggregate and 5kg of agricultural fertilizer.
“New Providence produces 800 tonnes of garbage a day,” says vice president of business development Bradley Smith. “If we convert half that we can provide five per cent of BEC’s requirements.”
Although all the details of the various proposals have not been disclosed, Smith believes that Plasco was the only company to commit to a pure gasification process. The others appear to have incorporated older technologies, including simply burning the waste.
Ginny McKinney, of Bahamas Renewable Energy Resources, says, “gasification is our preferred technology, but we felt we had to give BEC options. The main thing is to start getting rid of garbage, with most bang for our buck.”
Plasco has a proven, commercial scale optimization plant in Ottawa, Canada, that represents its 100 tonne-per-day modular string design.
A greener future
Yet BEC’s financial stake in any of these schemes will be negligible. The companies involved will make all the capital investments, with BEC acting as a guaranteed customer, and having to spend on the order of a few million dollars to modify its grids.
There is no financial reason why BEC shouldn’t opt for the most exciting, if unproven technologies, and there are many good ecological reasons why it should. It is a government-owned company, however. Any failed projects will have a political legacy, and this creates a pressure towards conservatism.
Whatever route is chosen, in the short-to-medium term (10 to 15 years) no more than 10 per cent of The Bahamas’ electricity will come from alternative technologies. The Bahamas is projected to import 7.5 billion barrels of oil a year for the foreseeable future (at a cost, in 2008, of $1 billion). Seeking out a practical alternative to such a costly (and finite) energy resource is quickly becoming a priority for both the private and public sectors.