500 MW Wind Farm Proposals for Bahamas

by Larry Smith

In 2003, a New Mexico company called WindErgy proposed a massive wind farm project for the Bahamas that obviously went nowhere.

The proposal was revived in 2006, again without success. It offered to build two 500 MW wind parks (on Abaco near Snake Cay and on Eleuthera near Hatchet Bay) with a potential net output for each of 176.3 MW - enough to generate 1.5 million megawatthours of electricity annually.

Each of the 250-turbine wind parks would have been the largest such operation in the Caribbean, able to have more than completely displaced all the generation capacity on New Providence.

According to the 2006 proposal document, the anticipated generating capacity was based on "exhaustive research of the average annual wind resources on Abaco, Eleuthera, and Exuma". WindErgy said it would be able to find the $2 billion needed to finance the project. No government investment was required.

In order to prove the feasibility of these projects, WindErgy produced detailed research of wind resources accumulated by the National Oceanographic and Atmospheric Administration (NOAA) and The Bahamas Department of Meteorology.

The gold standard for financial viability of a wind farm is documented wind speeds of 5.9 meters/second (Class 4). WindErgy presented research showing at least Class 5 wind resources on both islands, with the exception of August on Abaco, which recorded Class 3 speeds.

Wind power parks take up a lot of landmass, but the actual footprint of a turbine is only 314 square feet. Parks can consist of wind turbines in a row, separated by at least five diameters of their blades, or they can be located in multiple rows separated by up to eight rotor diameters. Turbines are always sited perpendicular to prevailing winds.

A typical 500 MW wind park with 250 2 MW turbines configured in a single row could extend for 62 miles and occupy 2,150 acres.  A similar wind park configured in two staggered rows might occupy 8,618 acres.

The WinErgy project would have wholesaled electricity to Florida Power & Light via an undersea cable from Abaco to Grand Bahama and between Grand Bahama and West Palm Beach, Florida. Power would also have been provided to BEC via undersea cable from Alice Town, Eleuthera to Winton on New Providence.

Both wind farms would have taken 18 months to complete. WindErgy was seeking a 25-year concession, after which the development would have been transferred to the  government. In its 2006 proposal, the company said construction could begin as early as August of this year once government approval had been obtained, but this was not forthcoming.

WindErgy's principal is Larry Richardson, an electrical engineer with over thirty-five years of experience in operations and management of complex infrastructure projects with Fortune 500 companies like Lockheed Martin, Black & Veatch, and the US Army. He was a corporate representative to the World Bank and the US EXIM Bank, and has served as a consultant to the Department of Energy, the Nuclear Regulatory Commission and the Strategic Petroleum Reserve Office.

The company says it is in the business of wind turbine manufacturing, wind park development and operations, and sales of wind-generated electrcity to regional and national grids. WindErgy’s engineers have modeled over 21 wind parks in the United States, as well as in Taiwan, China, Canada, Scotland, and Central America.

Comments

[Doug Cotton]

A single 500 MW wind farm would be a large project, generating more than
the BEC could reasonably use. When the winds are blowing strongly, this
would more than completely displace all the generation capacity on New
Providence which would cause major system integration problems for BEC.

It seems to be set up more to sell power into the Florida market
although one would want to locate the wind farm closer to Florida - on
or next to Bimini in shallow water. With more than 1 farm, you would
have to sell power to Florida.

The major disconnect I see is with their wind power estimates. Their
data estimates higher levels of wind on Eleuthera than the NOAA data we
used in our report - a low of 4.1 to a high of 5.4 m/s, with about 4.5
m/s on average. One could argue that the NOAA data is not a reliable
indicator and site specific information may show different results, but
Cape Systems says that their data shows average wind speeds of about 4.5
m/s at 100 feet. As stated in our report, the typical cut-in speed for 2
MW turbines such as described in this proposal is 4 m/s so it is hard to
imagine they would obtain the capacity factor they cite.

[Sara Parker]

We are interested in building a windmill to run our house on the eastern tip of New Providence. Does anyone know of such a product in use here? (My grandparents used a simple one to pump water in Missouri.)

I have heard that wind fields are terribly destructive to bird life. Bill Bardelmeier has a very interesting alternative proposal.

[larry smith]

Compared to what? Hitting birds with automobiles (along with other wildlife)? Birds killed by cats? Birds hitting buildings or phone towers? Birds killed at airports? Quite possibly, a higher mortality of birds will be attached to the transmission wires needed to get the wind power to market.

In the United States, cars and trucks wipe out millions of birds each year, while 100 million to 1 billion birds collide with windows. According to the 2001 National Wind Coordinating Committee study, these non-wind mortalities compare with 2.19 bird deaths per turbine per year. That's a long way from the sum mortality caused by the other sources.

Please see this page...

http://www.awea.org/faq/sagrillo/swbirds.html

[larry smith]

As for single ghome wind turbines, see the following...

http://www.awea.org/faq/rsdntqa.html#TurbineSizing

[Bob Knaus]

Larry. You're a journalist. You know the principles of investigative reporting. You have a reputation as a tough reporter. That's why your column is named Tough Call, right?

So why do you keep swallowing the numbers presented by environmental advocates without questioning? For cryin' out loud, do some basic checking for math consistency and factual accuracy.

5.9 m/s is Class 2 not Class 4. Here's a link: http://www.awea.org/faq/basicwr.html

There are several others that will tell you the same thing. It's important, because available wind power varies with the cube of the wind speed. The northern Bahamas is not really that great of a spot for wind generation. I know; I spend a lot of time there listening to the one on my boat make electricity.

Speaking of which, in five years of more-or-less continuous operation, it has hit two seagulls that I know of. Didn't kill them; but in both cases it knocked enough primaries off a wing to make them unable to fly.

[Art Sands]

Bob thanks for the link according to the chart 5.6m/s to 6.0m/s at 10 meter measurement are class 4 winds.
Also to correct the intial article the 2 parks were to be connected from NP to Eleu to Abaco to GB to Flroida following the currentt routes that both BTC and Cable crossings use.

[larry smith]

In this case, Bob, I was merely reporting on the contents of a proposal document, not trying to analyse it. It did not occur to me that basic data would be falsified to risk a $2 billion investment.

I did, however, ask an independent expert to review, and Doug's comment is posted above.

I should have noted that the speeds lifted from the proposal refer to wind class at the 100 meter level and translate into over 14mph on average for Eleuthera and over 16mph on average for Abaco.

These are calculated speeds for that height based on average measured speeds of 12mph for Eleuthera and 14mph for Abaco at the 10 meter level.

The proposed turbines had a hub height of 100 meters and a rotor diameter of 80 meters.

Art may have additional information, but the document describes an undersea cable from Eleuthera to Nassau and from Abaco to Grand Bahama to Florida:

"If BEC does not commit to purchase the power from the Abaco project, WindΣrgy’s intent is to sell it to Florida Power & Light. To do so, would require negotiations with Grand Bahama Power to use its distribution lines to route the output to a substation to be built to terminate an undersea cable between Grand Bahama’s west end to West Palm Beach, Florida, paralleling the AT&T submarine fiber optic cable between those two points. Previously, Grand Bahama Power expressed a desire to purchase a limited quantity of the proposed Abaco wind project’s output.

"Conversely, WindΣrgy would build an undersea cable between Abaco’s BEC substation on its southwest end to a BEC Nassau load center."

If Art does have more info perhaps he could share it.

[Bob Knaus]

OK, so a bit more mental math... hub height of 100 meters and rotor diameter of 80 meters = 180 meter height. That's almost 600 feet tall. And there would be 250 of them. How far do you think they would be visible?

The lower Florida Keys have a better wind profile than the northern Bahamas. Wouldn't it be more efficient to locate the turbines there, if you're going to produce for the Florida market? What do you suppose would happen if someone proposed a chain of 600-foot wind turbines along the Keys? The residents would raise a ruckus! They might cite any number of causes, but fundamentally they would not want such huge machines to impinge on their view of the sea.

Should the Bahamas be the outsourcer for Florida's visual pollution?

What do you think the folks in Abaco and Eleuthera would do if this proposal started to get serious? Their #1 industry is tourism. Do you think they would be any happier than people in the Keys to see giant turbines sprouting along the coast?

Don't get me wrong. I'm all in favor of green power. I make most of my own. I just think it needs to be tempered with a dose of reality.

[larry smith]

Again, I was sharing the contents of a proposal - not necessarily advocating it.

Your point is obviously valid (and is the same argument used against siting LNG facilities off Bimini). But it has to be weighed against the cons for the Bahamas of continuing with conventional oil-fired generation.

[larry smith]

BTW, Bob, I believe you made at least one mathematical error. If the rotor hub (point of attachment to the support) is 100 metres and the rotor is 80 metres diameter (40 metres radius), the bottom tip of the rotor will be 60 metres above ground and the top tip of the rotor 140 metres above ground. It's still a big mother.