David Hall, VP power systems UK & Ireland at Schneider Electric, explores why utilities need to be smarter when selecting switchgear and outlines the advantages of embracing the latest innovations generating change in the offshore wind sector.
Climate change represents one of the most major challenges we face as a planet today – one that spans social, economic and ecological impacts. As the UK continues to move towards more sustainable energy sources, it needs to keep up its growth in order to succeed in its target of reducing the carbon intensity of energy generation to 50-100g CO2/kWh.
In order to meet these targets, the UK government is committed to building an additional 2GW of offshore wind capacity by 2020. This means that in just under a year, wind power could generate a fifth of power in the UK. In addition to its environmental credentials, building offshore wind turbines is cheaper than investing in new gas or nuclear power stations.
Last year, almost a third of the UK’s electrical energy came from renewable sources between July and September, as wind turbines alongside solar panels helped achieve a quarterly record for green energy. 2018 was a good year for wind power in general, with records being broken during ‘the beast from the east’, and Storm Diana.
A new challenge
While the transition to renewables is good for the environment, it will be a challenging one for utilities. As the country continues to reduce its reliance on fossil fuels, utilities companies are under greater pressure to improve the efficiency and reliability of their power supply and ensure it is future proof. After all, a green and reliable supply of energy is the foundation on which smart industries run and economies grow. Yet the growth of offshore wind poses new and unfamiliar challenges.
More support and funding means offshore wind farms are growing larger, and more innovation in the space means that they can be installed further out to sea. Turbines are also increasing in size to generate more energy, with 10MW+ machines likely in the future.
Whilst more renewable energy is of course vital, the drawback of large farms is that bigger turbines and longer cables are required to connect the generated power to the grid. Longer cables in particular can lead to inefficiencies in transmitting the generated energy, meaning that the energy that is generated at the turbine may not fully reach the shore to be added into the grid.
One of the keys to keeping the system efficient is investing in the latest switchgear technology. Without an innovative approach to high-voltage switchgear, utilities run the risk of more expensive equipment and more frequent power losses.
Making the switch
Traditional 72.5kV switchgear is costly, heavy and intended for the transmission of power from generation site to electrical substation. It can no longer scale with the complex demands of our burgeoning offshore capacity. As such, a new generation of 72.5kV equipment has been developed, conforming to all the applicable High Voltage standards, but with all the benefits of a Medium Voltage switchgear.
Utilities have to be smarter when selecting switchgear and should not be afraid of more innovative solutions. New designs have been built to be future proof. For easier transportation, installation and maintenance they should prioritise solutions that are compact and lightweight. New innovations also boast strong safety advantages, such as certified internal arc rating, which was not designed into previous solutions.
The latest solutions are also designed with a modular approach, allowing individual panels to be arranged as a switchboard via a common busbar. This provides multiple configuration options, providing greater flexibility.
Another development is the use of connected technologies from the Internet of Things (IoT). IoT technology is crucial for the smooth running of modern networks, and the latest solutions are IEC61850 autonomation ready, featuring digital protection relays, condition monitoring of cable connections, humidity, temperature and gas-pressure monitoring all with remote, real time value indication. This all helps to ensure solutions are as resilient as possible, staying in good condition in harsh environments, particularly as maintenance at offshore facilities can itself be challenging due to ever-changing weather conditions.
For improved cost efficiency, utilities should seek out switchgear with maintenance-free high voltage parts including sealed-for-life vacuum interrupters. Purchasing equipment that comes as a complete unit will also keep installation costs from spiralling.
Above all, they should take advantage of digital innovation. The latest generation of switchgear contains Internet of Things connected sensors, protection relays and discreet devices that offer real-time condition monitoring. Embedding the common protocol of IEC61850 enables this to be achieved quicker and more cost effectively than established solutions. A reduction in supply failures and an increase in equipment lifespan can mean an offshore generation facility suffers less down time due to maintenance. With unreliability of supply being the age-old criticism of wind power, this move brings wind one step further towards full integration into the grid.
By embracing switchgear innovation, utilities and operators can meet the demands of our diversifying energy mix. The potential of offshore is enormous, it only needs continued support and creativity to help it reach its second wind.
