Bahamas Pursuing Renewable Energy Projects

by Larry Smith

The Bahamas Electricity Corporation is inviting proposals for renewable energy power purchase agreements in several technologies, officials have told Tough Call.

Although there has been lots of talk before, this marks a dramatic policy shift. It is driven by fear that escalating oil prices and supply problems could disrupt the Bahamian economy. International concerns about pollution and climate change are also a big factor.

The pending Request for Proposals follows the appointment of a special committee at BEC to research the most viable renewable energy technologies for the Bahamas at utility scale. This group is headed by Jerome Elliot, a senior engineer, and includes Brian Taylor, Robert Hall and Errol Davis.

They have identified the most promising alternative methods to produce electricity for the Bahamas. These candidate technologies include solar panels (especially concentrating trough collectors), hydrokinetics (including ocean wave and tidal systems), thermal conversion (such as OTEC and biomass systems), gasification (including the capture of biogas from landfills) and wind turbines.

"We are not yet at the point where renewable energy is an economic alternative at utility scale," BEC Chairman Fred Gottlieb told me in a recent interview. "But this may come sooner rather than later given the escalating cost of fuel. Our challenge is to get up and running to prepare for that point. The committee has put lot of effort into this - we are not just dabbling. It is a part of this government's strategy and it is being actively pursued."

BEC supplies 85 per cent of all Bahamian consumers, with an installed capacity of about 400 megawatts. Grand Bahama Power Company has an installed capacity of about 140 megawatts. The cost of imported oil to generate electricity in the Bahamas is now around $800 million a year. And there are currently planned investments of hundreds of millions in new oil-fired generators for New Providence. Abaco, Eleuthera and Bimini to meet rising power demands.

"Unfortunately, renewable energy options cannot meet the present rising demand on these islands," said BEC general manager Kevin Basden. "But we are looking to form public/private partnerships with RE firms. I am an engineer with 27 years experience at BEC and I totally support these efforts, but it has to be properly managed."

According to the committee, BEC's long-term planning must seek to replace conventional fuels with some combination of renewable energy technologies. A ratio of at least 9 megawatts of conventional power to 1 megawatt of power from renewable sources has been proposed.

Among the most promising alternative technologies for Bahamian conditions is concentrated solar power, which focuses sunlight onto a receiver tube to heat a fluid which produces steam to drive a turbine that generates power.

This is the most mature solar power technology, having been in use since the 1980s. Six gigawatts of capacity are now under development around the world. However, these plants typically require up to 500 acres of land for utility-scale generation, which makes them more appropriate for the less-developed out islands, connected via undersea cable to New Providence.

At least one prospective investor - Renewable Energy Holdings of the United Kingdom - has offered to finance a submarine cable from Eleuthera to transmit electricity produced by sunlight, ocean waves or wind - or some combination of each. REH is a publicly traded company led by Sir John Baker, who managed Britain's electricity privatisation and restructuring programme.

The company owns or is developing wind farms in Germany, Poland and Britain. It also owns a landfill gas project in Wales and has developed advanced wave power technology that pumps high-pressure sea water ashore to supply a reverse osmosis desalination plant, or to generate zero-emission electricity.

REH has offered to build such a plant off the Atlantic coast of Eleuthera, and BEC officials are planning to visit a prototype plant in Australia where this technology is currently being tested.

Before its viability was threatened by the withdrawal of a major partner, the Baha Mar resort development on New Providence had proposed using OTEC technology to provide air conditioning to its waterfront hotels. The Bahamas is considered an ideal location for OTEC plants, which must be within the tropics, have a steep drop-off where the ocean plunges to over 3,000 feet, and be close to a power grid.

An OTEC plant pumps warm surface sea water into a tank. The air in the tank is pumped out to create a vacuum, which vapourises the water. The steam can be used to spin a turbine to generate electricity, and then passes through a heat exchanger where it is condensed - by cold water pumped up from the ocean - into fresh water.

BEC officials say that although this technology is very capital intensive and still in the development stage, utility-scale joint ventures with developers could be "cautiously explored". The Baha Mar OTEC cooling project would have cut the resort's projected 23 megawatt electricity demand by half, experts say.

Wind power is the world's fastest-growing renewable energy technology with global capacity currently at about 94 gigawatts, but proposals for wind farms in the Bahamas have fallen on deaf ears in recent years. One reason is because BEC's investigation of wind resources in 1991 concluded that the costs did not justify an investment in utility-scale generation. But that view has now changed.

"In the intervening years, all of the previous objections (to wind power) have been overcome," the BEC committee said, "save that of the visual impact of the turbines."

To understand what that means, a few years ago an American company proposed building two large wind farms on Abaco and Eleuthera, each with 250 turbines on thousands of acres of shoreline. The 2 megawatt turbines would have stood 450 feet high. But this has to be weighed against the cons of continuing to rely on fossil fuels.

The BEC committee has called for a re-examination of the country's wind resources in the light of current technology and costs. They also recommend construction of a pilot wind farm on the out islands, and suggest that a hybrid wind farm and wave power plant could supply all of Eleuthera's energy needs. BEC officials plan to visit the 23 megawatt Wigton wind farm in Jamaica to see how the turbines stand up to hurricane conditions.

Biofuel was not seen as a viable solution for power generation in the Bahamas, but a small production plant being established in Nassau by Bahamas Waste and Cape Systems could produce sufficient quantities from used cooking oil to run BEC's diesel vehicle fleet. As the committee report points out, burning biofuels will not eliminate carbon emissions, and large-scale use will require continued reliance on fuel imports.

The committee's preliminary recommendations call for BEC to build experimental solar power facilities at its Blue Hills and Clifton Pier sites, to explore wave technology, to plan a pilot wind farm, to explore further co-operation on solar power with Cape Systems on Eleuthera, and to study the possibility of consumer-scale implementation of solar photovoltaics through net metering.

According to General Manager Basden, BEC will also revisit the installation of solar street lighting, which was tried in Nassau on an experimental basis some 15 years ago but never pursued due to maintenance problems. BEC's substations and public parks on New Providence may also be fitted with solar lights.

And the corporation is promoting energy efficiency at customer education events around the country. The first energy fair was held on Abaco recently and the next will be on Eleuthera. The idea is to push conservation measures that ordinary consumers can take - like replacing old-style bulbs with compact fluorescents. Experts say that such measures alone could reduce our energy costs by a third.

One technology that the committee did not explore was the production of energy from garbage. But at least two firms are already pursuing multi-million-dollar waste-to-energy projects with the Ministry of Health, which is responsible for landfills and solid waste collection and disposal.

Innviron is a Florida-based firm that manages more than 40 solid waste facilities worldwide, including landfills, compost plants, recycling facilities, and hazardous waste treatment and disposal facilities. Innviron wants to sort and ship metals, plastics and paper for recycling overseas, compost organic waste, and capture landfill gas for energy production.

Meanwhile, a local group called Bahamas Renewable Energy Resources (headed by Waste-Not Ltd's Ginny McKinney) is proposing a thermal conversion process that will virtually eliminate landfills, compost organics and convert most solid waste to a non-toxic slag that can be used in road-building and block-making.

"As we reduce garbage by 90 per cent we will be able to power over 70,000 households on New Providence," Mrs McKinney told me, "as well as making millions of gallons of potable water through distillation."

Oil prices are expected to remain high and geopolitical issues are likely to cause supply disruptions, so it is more urgent than ever for small island developing states like the Bahamas to begin shifting their energy economy away from fossil fuels.

The plain fact is that within 20 years we may be unable to afford to buy the oil to run our economy. We currently spend almost one sixth of our GDP on fuel imports, and by all accounts that price tag will only go up. And if the tanker doesn't come, the country will shut down.

To cut our dependence on fossil fuels requires aggressive energy conservation in the short term, as well as a policy framework to encourage research, development and investment in a range of alternatives.

Another government-appointed committee, headed by Philip Weech, the new chairman of the BEST Commission, is looking into changing the legal and financial framework to provide for private power generation and net metering, and to promote investment in renewable energy.

Comments

[C.Lowe]

HI Larry, there is a technology that could be ideal for us at the consumer/commercial level, which is the sunshine tracking stirling engine dish which produces up to 18kw per 18 ft diameter dish.
While there is an effort to set up a multi dish system in California to produce some gigawatts, it uses a technology that predates the steam engine.
If you search solar stirling engine you will find it on the web.
I would take my house off the grid with one of these in a flash!
Sun in the day, charged lithuim polymer batteries at night.
Of course we would need to change the legislation to permit off grid, or do net metering.
The pressure is mounting

[C.Lowe]

Hi Larry, this is the site
http://www.stirlingenergy.com/default.asp
Check it out

[C.Lowe]

For an explanation of the Stirling engine principal, go here
http://www.keveney.com/Stirling.html
Now, imagine creating a greater heat differential with sunshine v. cold sea water from the depths.
This would generate greater than 18kw per dish, which is achieved with air colling.
Also, if LNG regassification were to take place in Freeport for instance, the cold seawater used for the regassification could also be used to increase dish output potential.
I have a german made Sterling engine, which is quite a treat to watch in operation. A magnifying glass works wonders.....

[Bob Knaus]

I hate to be the guy who is always pointing out innumeracy in others... but I'm pretty sure that the claim for the Stirling engine is 18 KwH per day, not 18 Kw instantaneous.

An 18 foot diameter dish = 5.25 square meters. This image on Wikipedia shows a 5 KwH/day rate of insolation in south Florida. That will give you about 26 KwH/day from the 18 foot dish. It would take a damn efficient Stirling engine to extract 18 KwH/day from that... but maybe!

It sure won't replace an 18Kw Onan generator.

[Bob Knaus]

Oops - forgot the link:

http://en.wikipedia.org/wiki/Image:Us_pv_annual_may2004.jpg

[C.Lowe]

Check the site Bob, but my onderstanding is 18kw output ac, with full sunlight, and can by sync'd directly to the grid.
The farm project in california is geared to produce a few gigawatts, with dishes in the hundreds.
I have communicated with them, but they are focused on that project right now, and dealing only with governments.
I suppose that dooms us to denial, right?

[C.Lowe]

One dish on an annual basis can produce 55,000-60,000 kWh of electricity. This is equivalent to the total energy required for 8-10 homes in the U.S.

This is from their site, FAQ section.
I saw one of these in Las Vegas, I believe a U of Nevada project.
It is real.

[Thomas Bjelkeman-Pettersson]

Bob Knaus, your calculations are not right.

1 foot = 0.3048 m
18 feet = 5.4864 m
5.5 m dish => PI * radius ^2 = 3.1415 * (5.5/2) ^2 = 23.76 square meters (not 5.2 square meters)

According to this diagram:
http://www.stirlingenergy.com/incl_docs/Solar_overview_incl_files/image002.gif
If you have 5 kWh/sq m insolation then you get about 1.2 kWh / sq m generated energy.

The Sterling Engine Systems Inc. dishes are 37 foot. http://www.stirlingenergy.com/faq.htm
Which can be seen on some of their pictures:
http://snurl.com/23cbb

So they would have an area of about 100 sq m. With 1.2 kWh / sq m, that is about 10 kW output during daytime (12 h) on average in my back of the envelope calculations.

[C.Lowe]

My mistake on the dish size, there was another company whose dish was 18 ft, with a stirling engine generating unit
Solo Stirling Gmbh which became Solo Stirling Systems Gmbh, but their site is down.
It did say they were out of funding for production, and rights etc had been sold.

[drew Roberts]

We definitely need to change the legislation. Now. If we can supply our own power either more reliably or more cost effectively than BEC, why on earth should the government FORCE us to buy from them?

Now is the time to at least look into off grid solutions. Or partially off grid solutions.

And make low power tech more affordable via duty rates while we still have duty to play with.

all the best,

drew

[Mike Russell]

The shallow waters on the south side of Nassau are a perfect location for a wind farm. Basically out of sight and not using valuable land area.

[drew Roberts]

"Basically out of sight and not using valuable land area."

Out of site from whom? People live on the south side too. I used to be one of them.

all the best,

drew

[Noel Rodman]

Check out my house at 182 Sandyport Dr. Nassau. I have installed 20 BP 170 Watt panels and tied them in 2 strings to an SMA 3400 Watt Inverter. I produce about 18Kwh per day/average to subsidize my monthly power bill. I would love to show other Bahamians how they can do this to bring down the cost of power and also get BEC to credit my overproduction back to the grid. Any suggestions on how to do this? Thanks, Noel Rodman

[Mike Russell]

Come on Drew, be smart. The wind farm could be placed off-shore far enough that yes it would be visible but not be a major eyesore. We as part of the human race are going to have to compromise or perish at our own hands.

[Mike Russell]

Noel please contact me at chubasco@coralwave.com . With almost a $1000.00 a month electricity bill, I am very interested in what you have done with the solar panels and inverter.