What’s a sustainable island?
An island is sustainable when it can meet demand for water, waste, food and energy with self-sufficient processes. Island communities face unique challenges when meeting these demands, often relying heavily on expensive imported resources and inefficient processes. By finding more sustainable solutions, islands can reduce their environmental impact and increase their efficiency and balance of trade.
In the energy sector, Scotland has an excellent reputation for the development and integration of new renewable installations and policy development. There are several case studies that demonstrate Scotland’s success in managing off-grid and island constrained networks.
As our own projects in constrained power networks have shown, power flows can be actively managed at minimal upgrade cost, using smart grid technology to balance renewable energy with diesel generators. Not only does this reduce the power costs for governments, but it also defers major electrical infrastructure upgrade costs until after some benefits have been realised –easing government finances.
Scotland has a world leading example of optimising wind, solar, marine and diesel on the island network of Orkney. This is an extremely difficult combination to control and Scotland has know-how and expertise to export this knowledge and offer solutions to other island nations, for both remote areas and within cities.
Not just renewable energy
In other sectors, Scotland’s policies on Zero Waste, water, sewerage, and resource efficiency are among the most progressive in the world. This fosters innovation: for instance, the district heating and cooling company Star Renewables is one of the only companies in the world that provides a 300% efficient district heating scheme. ( it uses 4MW of electrical energy for 12 MW of renewable heat to an industrial, residential and commercial district of Norway). The same system can be adapted to introduce district cooling in hotter countries. Elsewhere, the Scottish Biofuel Programme, Hydrogen Association (SHFCA), and the Scottish agricultural and education sectors give further dimensions and possibilities that other countries do not have.
Scotland’s expertise in animal husbandry and aquaculture is incorporated into the sustainable island concept, and can be used to develop food and energy capacity on an island. For instance, the Scottish Agricultural College has developed and implemented model farm concepts for Cuba, designed around food and crops for energy. From this work, a Scottish engineering company developed a front end for a harvester to remove a woody biomass plant in Cuba, showing the benefits of cross-sectoral approach.
In the water and sewerage sector Scotland has technologies that can give an integrated solution across sectors – using byproducts and energy from one process to fuel another. For example, a Scottish desalination process for drinking water for an island may use less energy if it is combined with heat extraction from sewerage processing and a high efficiency heat pump. A byproduct of this process creates chilled district cooling water to replace electric air conditioning for hotels. In this way, cross-sectoral processes can be linked, reducing energy needs and improving energy efficiency for the country.
The Orkney Islands smart grid
Scotland has specific experience in making islands more sustainable, having successfully implemented smart grids, new forms of energy storage and efficient water management. The Orkney Islands have a population 22,000 and a limited cable connection to the mainlaind of 48MW. The islands have both large and small scale generation wind systems, with over 600 small-scale turbines on the grid. The islands needed a way to increase energy supply, and installed a smart grid instead of a new subsea cable.
The Orkney Islands grid was the first network in the world to link an energy storage system with the integrated output from solar, wave, wind and tidal electricity generation. Smarter Grid Solutions (SGS) ran the project, introducing intelligent control software and hardware to control energy generation more efficiently, and thereby add 20MW to the system. The project cost £500k, whereas installing a new subsea cable would have cost £30m.
Over the last ten years the Scottish utility company SSE has worked with the University of Strathclyde on the development of the world’s first Active Network Management system on the Orkney Islands. The system has been operational on Orkney for over three years and is the first of its kind in the world. SGS have introduced a suite of application products for utility companies to control renewable generation on their networks and extend grid capacity by 200-300%. And while every island context is different, their methods can be widely applied in both hot and cold climates.
The smart grid plays an important role in connecting energy generation to energy storage, but what about the energy storage itself? In 2013 the Orkney smart grid added one of the largest energy storage systems in Europe, a 2MW lithium ion battery from Mitsubishi Heavy Industries.
Taking things a little further, the Isle of Eigg is completely off-grid, and uses a battery storage system alongside its diesel, wind, hydro and solar energy generation. Elsewhere, the Isle of Gigha will introduce a Vanadium flow battery system in 2015, while the Pure Energy Project on Unst in Shetland has already introduced hydrogen generation and storage. These instances demonstrate a willingness to test new technology, and each one gives Scottish companies the experience to offer solutions abroad.
Water management is an important aspect of the sustainable islands approach. Scottish Water has invested £5.5 billion in new technologies and ways of working. It has reduced operating costs by 40%, and it has an international consulting arm - Scottish Water International – is advising utility companies and governments in the Middle East on water management strategies and best practice.
What are the benefits?
Perhaps the most important benefit of the sustainable islands approach is that it minimises reliance on oil markets and oil price changes. This can lead to improved levels of sustainable economic development and improved energy security. Other clear benefits include the more efficient management of water and sewerage resources, improved air quality and the development of a low-carbon society.