A British company maintains that the creation of an offshore wind farm is an economically feasible and environmentally sound project, in response to doubts raised by a mechanical engineer.

BVG Associates, a strategic consulting provider, was commissioned by the environmental charity Greenrock to carry out feasibility studies on the farm’s potential in Bermuda.

The firm previously found that the renewable energy model could reduce electricity costs by a third.

However, Jan Card, a mechanical engineer, believes the offshore wind farm being explored by the Regulatory Authority, which launched a procurement process this month with the issuance of an expression of interest, could end up costing the consumer more.

Adding together variables such as insufficient wind speeds and relatively low energy demand, Mr Card said, the kilowatt-hours from the windmill would be anywhere from 10 per cent to 30 per cent more expensive than a Belco-generated kWh.

The RA said that the project was expected to be rolled out in phases, beginning with an initial installed capacity of 60-megawatt, expanding to 120MW.

The RA's Integrated Resource Plan, a blueprint for Bermuda’s future energy mix, has indicated that a 60MW offshore wind farm combined with 40 to 85MW of solar photovoltaics, and balanced by a mix of battery storage and fossil-fuel generation, was at present the optimal generation mix for Bermuda in terms of cost and emissions reductions.

Greenrock has said it is largely supportive of a proposal for a 60MW wind farm.

However, Mr Card said Bermuda as a location for such a farm was “suboptimal” owing to local costs for future wind and sea-floor studies, and said that alternative renewable energy options should be explored.

BVG Associates maintains that the project is sound, saying that options for Bermuda’s energy mix have been explored for 25 years.

In a joint statement with Greenrock, BVG said: “Solar and wind technology have consistently featured as leading technologies due to their commercial maturity and Bermuda’s good solar and wind resource, which means they can generate electricity at a lower cost than using fuel oil.”

Fuel oil is the fossil fuel used predominantly by Belco to generate the majority of the island’s electricity.

Mr Card wrote an opinion piece on the issue for The Royal Gazette in 2023 after a town hall meeting on offshore wind.

At roughly this time, Greenrock commissioned BVG to carry out a parallel set of studies, which the company said, in some cases, reached different conclusions on topics such as the turbine size, location and cost of energy.

Mr Card said his conclusions in 2023 were not substantially different from now.

He said: “My reading of the BVG Associates’ second pass is that the conclusions are not qualitatively different.

“It seems the factors have been arrived at in a somewhat subjective and anecdotal fashion, and are not grounded in experience or data representative of transferring the model context from the North Sea to Bermuda.

“My conclusion is that the LCOE results [the ”levelised cost of electricity“ or the present value of total cost over the project lifetime] must be taken as estimates with relatively large margins of error.”

Attendees of a town hall meeting in 2023 were told that the project, which is slated to be completed by the end of 2029, could cost between $250 million and $450 million.

They heard that it would generate about 30 per cent of the annual electricity demand in Bermuda.

Greenrock commissioned BVG to model the LCOE from an offshore wind farm in Bermuda in 2022, and this was later updated in an Annual Energy Production Analysis that was commissioned in 2023.

The analysis used long-term wind resource data purchased from Vortex, specialists in atmospheric modelling for wind resource forecasting.

BVG and Greenrock said: “These studies showed that offshore wind turbines could generate electricity in Bermuda at a commercially competitive cost, which was significantly lower than the cost of electricity generation from fuel oil or LNG.”

The analysis provided by BVG considered Bermuda's remote location and the scale of the project.

Mr Card said: “My point with respect to the predicted costs is not that they were wrong in some specific way due to bad inputs. Rather, it is that these are modelling estimates and need to be treated as such.

“Anyone familiar with large projects, especially first-of-a-kind projects, will know that early cost estimates are always low, often by large margins.”

The RA’s preferred site for the farm is nine kilometres north of St George’s Island.

A recent pre-feasibility independent study found the site to be “technically suitable and economically promising”, with no major environmental concerns identified.

Mr Card said, in concurrence with BVG and Greenrock, that sites excluded by the RA's own consultant firm, Ricardo, should be reconsidered, not least on the southwest platform.

BVG was commissioned by Greenrock to carry out a location assessment for offshore wind in 2023.

BVG and Greenrock said: “This indicated cable routing and access for maintenance would be more challenging, and therefore costs would be greater, for sites to the southwest of the island.”

However, they added: “Greenrock’s spatial assessment in 2023 discounted the RA site as it only works for a scale of turbines no longer used offshore.”

The RA said it would be commissioning more studies including a seabed study.

Mr Card said costs for such studies could be incurred by developers.

He added: “As to the commitment to perform the wind and sea-floor studies, this too is premature. These studies will be location-specific.

“The RA should invite the interested parties to participate jointly in such data gathering and invite their input as to scoping and methods.

“The recommendation that we spend another $4 million to refine the wind data and study the sea floor for a wind farm project is a waste of funds that should be directed elsewhere.

“Investigating the sea floor may save a developer some money but will also not improve the final analysis.”

BVG and Greenrock said the collection of revenue-grade wind data was established practice in the offshore wind industry and is necessary to secure project finance.

They stated: “Other local sources of wind data, though fit for purpose for their original use, have been considered but have higher associated uncertainty than needed to finance the project.”

Once the expression of interest process is completed, there will be a request for qualification and then an invitation to tender.

Interested parties can find the expression of interest and related documents on the RA’s website at ra.bm/offshorewindfarm.