Mane Energy Issue 6 - January 2017 | Page 8

CUTTING THE COST OF OFFSHORE WIND FARMS

The UK government challenged the offshore wind industry to reduce the cost of electricity from its wind farms to £100/MWh by 2020. Recent figures show that the industry is well on its way to reaching that goal. Offshore wind costs have fallen sharply in the last couple years and are estimated to keep falling. Competition between firms to land projects has driven costs down as Europe’s offshore wind industry continues booming.

Sweden’s Vattenfall won a bid at the end of 2016 to build two offshore wind farms in Danish waters, which experts claim are the cheapest yet. The winning bid was €50/MWh, which is among the lowest costs in the world for offshore wind power. The price is not directly comparable with UK offshore wind farms, as they exclude grid connection costs which can be up to €30/MWh. However, even with the added cost for grid connection, it is still significantly cheaper than recent UK deals which were around £120/MWh (€140).

Offshore wind is a relatively new technology, and naturally the costs are falling as the technology matures. As offshore wind farms continue to grow, prices are expected to fall accordingly. In 2011, between 5-10% of newly installed wind farms were offshore – last year it was closer to 30%.

One of the key drivers in the cost of offshore wind farms is location. There are several factors that can dictate the cost of an offshore wind project:

• Ground conditions on the seabed;

• Average wind speed;

• Average depth;

• Distance built from the shore.

Ideally, a wind farm would be situated on a level seabed, with an average depth of 30m and wind speed of 10m/s or higher, and built closer to shore allowing for quicker, easier construction and maintenance.

Cost reductions have also come in the way of increasing the turbine size. Increasing the size of the turbine reduces the need for more turbines to generate the same electrical output – reducing operational and maintenance costs.

Turbine capacity has increased from 0.45MW in 1991 to nearly 8MW later this year - with the rotor diameter increasing from 35m to 164m and a total height now at 220m for a single wind turbine.

OFFSHORE WIND WITHIN THE UK

“Offshore wind is on track to be cost competitive with other new forms of power generation by the mid 2020s. By 2030 offshore wind could supply 35% of UK electricity demand, providing over 50,000 skilled jobs."

- http://offshorewind.works/

The UK has made their support for offshore wind farms clear and they are a world leader in the industry. The UK is on track to have 10GW of offshore wind by 2020. This will be made possible with the falling costs of building offshore wind farms. The technology conitnues to become more cost-effective. By 2030 the capacity could potentially increase to 30GW and provide power to 35% of the UK.

The continued growth of offshore wind in the UK has created more UK jobs. Facilities and ports are being developed in coastal towns to better build and service wind farms for the duration of their lifetime.

COSTS OF AN OFFSHORE WIND FARM