The Engineer

The 2011 Energy & Environment Winner - CES

In-Depth

Highview’s scalable liquefying technology stores excess energy as a cryogenic fluid until it is needed.

Cryogenic energy storage (CES) pilot plant

Highview Power Storage, Scottish and Southern Energy, BOC/Linde, University of Leeds

Energy storage is critical if we are serious about replacing fossil fuels with renewable electricity sources. One of the key problems with wind, wave and solar power is their intermittency, so matching the unreliable supply of green electricity to our demand requires an intermediate step so we can save the energy in some form for when we need it. Additionally, those countries whose traditional infrastructure is struggling to meet demand could benefit hugely from a back-up system to help accommodate peak consumption.

At the moment there are about as many methods of storing renewable energy as there are of generating it and, similarly, each has its own pros and cons. But engineers at UK Highview Power Storage have developed a potential solution to several of the sector’s issues by building the world’s first liquid air energy-storage system.

runners-up

The other shortlisted candidates in this category were:

ICARES: Integrated Compressed Air Renewable Energy Systems

University of Nottingham, Thin Red Line Aerospace

The team from Nottingham University and Thin Red Line Aerospace developed an energy-storage system that uses fabric bags of compressed air designed to be held deep underwater as an inexpensive and on-demand method of capturing renewable energy. The hydrostatic pressure from storing compressed air deep underwater provides most of the force needed to keep the air contained and provides an energy-storage solution that can operate very close to offshore wind turbines. The fabric pressure vessels created by Thin Red Line were made from a weight-saving material originally designed for the aerospace industry, while the Nottingham researchers developed powerful analysis tools to determine where the pressure points were in the fabric structure.

Development of widely accessible organic solar-cell technology

University of Warwick, Molecular Solar, Warwick Ventures

The third-generation solar cells that originated in Warwick University’s chemistry department use organic photovoltaic OPVs that offer the prospect of low-cost, lightweight, flexible solar-generating material.

The cells are composed of thin films of a cheap and abundant organic semiconductor material that can harvest light from a large proportion of the solar spectrum.

These are mounted on a flexible substrate developed by Molecular Solar called FLEXIFILM and weigh less than one per cent of the weight of conventional silicon cells. The materials used can be cheaply mass-produced with minimal environmental impact because they are made from non-toxic compounds and are recyclable. Molecular Solar says its technology has the potential to reduce the cost of solar electricity generation and to make it competitive with conventionally generated electricity at the point of use.