Renewable Energy

RENEWABLE ENERGY A RENEWABLE FUTURE: WHAT’S NEXT FOR OFFSHORE WIND?

Nathan Neal, Sales and Marketing Director, Biral

With the UK generating more electricity from offshore wind than any other country, the wheels are in motion to produce 40GW of offshore wind, including 1GW of innovative floating offshore wind, in the blusterous parts of the seas by 2030.

Offshore wind farms are growing at pace, with the world’s largest farm based in the North Sea. This challenging environment will soon be supplemented by ‘floating solar parks’, which will boost renewable energy in Europe and help reduce reliance on Russian gas. Floating solar panels have already been successfully installed inland and near-shore, but panels deployed off-shore must be able to withstand harsher conditions such as high winds, strong waves and saltwater corrosion.

THE MOVE TO SOLAR

Projects like the North Sea will see photovoltaic panels floating several metres above the water. Once installed, they will utilise the same undersea cables that carry electricity generated by wind turbines ashore, meaning complex infrastructure is not required to set them up.

With the need for secure, sustainable and affordable energy now unavoidable, projects like these offer a solution to land scarcity and allow for combined wind and solar offshore facilities to be developed. For example, countries with lower wind speeds but high solar irradiation will still be able to benefit.

However, rising temperatures continue to cause severe weather conditions and wind turbine structures are constantly in danger of succumbing to lightning strikes. Factors such as installing extra equipment to monitor visibility, warning of the approach of severe weather and lowering risks for those working in close proximity must be considered.

VISIBILITY AND PRESENT WEATHER SENSORS

All wind turbine parks are equipped with aviation obstruction (warning) lights, which for several years created light pollution and led to residents objecting to wind farm development. To combat this, Germany has had legislation in place since 2004 which requires developers and manufacturers to install turbines with visibility sensorcontrolled obstruction lights. These visibility sensors constantly monitor the local meteorological conditions and when the weather varies, the light intensity for the warning lights is automatically adjusted to its surroundings.

For example, on clear days where the visibility is greater than 10km, the light intensity is reduced to 10%. When the visibility is measured at 5km or higher, the light intensity is set to 30%. At all other times of lower visibility, it’s set to 100%.

In addition to visibility data being used to control the obstruction light brightness on wind turbines, present weather sensors are often installed to enhance the readings. These sensors output the specific weather conditions being experienced by the sensor at the top of the turbine in addition to the visibility information. This is important when the turbines are subjected to freezing conditions and the blades can become coated in ice, which can greatly reduce its efficiency.

In most cases, the turbines must be shut down and blades de-iced before they can be restarted. Having real-time weather data allows the operators to either plan for this more proactively or start their blade heating systems to reduce ice build-up and eliminate downtime. closer towards the site. If a thunderstorm develops overhead, the first lightning strike will be very local and as there is no advanced warning, there is no protection.

In wind turbine applications, advanced warning of overhead lightning is of enormous benefit for installation teams, operation and maintenance staff. Turbines are prone to lightning strikes and all staff on-site need to be warned of a storm’s approach to make their way to a safe area. The same is true of offshore wind farms where the support vessels require warning of approaching storms to allow them to make the area safe.

THE FUTURE IS RENEWABLE

ADVANCED WARNING OF APPROACHING STORMS

In many applications, a thunderstorm detector is used to help protect people and equipment from the dangers of a lightning strike by providing advanced warning of a storm’s approach. This is especially true of tall structures sited on either exposed or flat landscapes where they are likely to initiate a lightning strike. Detectors which rely on lightning alone are only effective if the storm is already producing lightning at a distance before moving

With a renewables future under way, it is hoped that more is still to come in terms of what can be done with these structures. Following the announcement of the 10 Point Plan in 2020, the £12 billion project is already leading the country towards a ‘Green Industrial Revolution.’

Now two years on, we’re already seeing it being put into practice. The next few decades in renewable energy are set to be exciting, and with net zero deadlines in sight, the end result will boost renewable energy use in Europe for generations to come. www.biral.com/