Welcome to the second issue of Energy.
Concern about future energy supplies and debate about the options continues to be in the news. The UK Government published a white paper on energy1 following their energy review carried out in 2006. The key proposals in the white paper are
renewed efforts to promote energy saving and efficiency
measures to assist the development of distributed electricity and heat supplies
development of commercial-scale carbon capture and storage (CCS) for coal-fired power stations
facilitating the option of new nuclear stations, subject to the result of a further public consultation.
encouraging the market to deliver a mix of generating capacity, in order to reduce dependence on imported gas
an increase in the renewables obligation (RO) from the present 15% up to 20%, plus banding of the RO so that the developing renewables, such as offshore wind and wave and tidal power, receive more ROCs per MW of output.
There remains concern among engineers that the market may not deliver the mixed portfolio of generating stations that is desired and in the timescale needed. However, the task for engineers now is to deliver the energy efficiency, the new supplies and the rapid deployment of renewables, both electrical and heat energy, all within the framework set by government.
This second issue includes a briefing and four papers each addressing different aspects of energy.
Energy from waste (EfW) could provide a significant amount of both heat and electrical energy in the UK. The majority of residual waste which remains after recycling is currently disposed of in landfill. This is a waste of a resource which is renewable (in the sense that it will continue to be created) and which has the potential to provide energy. The briefing paper by Andrew Crudgington outlines this potential.
The paper by Norris and Bryden describes the European Marine Energy Centre (EMEC) in Orkney which provides sites and facilities for testing wave and tidal stream energy conversion devices. EMEC provides a facility for developers to test their devices in open sea conditions with grid connection and independent validation of performance. The paper includes an overview of the theory of wave and tidal energy, a description of the facilities provided and an update on the uptake of the test sites by device developers.
Solar photovoltaic (PV) technology is evolving rapidly but it remains much too expensive purely for generation of electricity in the UK, compared with grid-connected supplies. However there is increasing interest in the integration of PV systems into building fabric, such that the PV arrays provide an element of the building envelope and also on-site electrical generation. The paper by Bahaj et al. reports on a study to assess the embodied energy, carbon footprint and economics of various forms of integration of photovoltaic arrays into buildings.
The environmental performance of existing coal-fired power stations must be improved if the operating life is to be extended until new generating capacity is built. The paper by Bruder and Castleman describes a project to reduce emissions by installing a boosted over-fire air (BOFA) system at a UK power station. BOFA consists of a system of ducts with booster fans to deliver air above the burners. This has the effect of lowering the NOx (oxides of nitrogen) and CO (carbon monoxide) in the flue gas while minimising loss of combustion efficiency.
Storage of gas is important to providing security of fuel supplies. The paper by Raghavan et al. describes the design and construction of an underground cavern in India for the storage of LPG. The cavern is located in hard rock at a depth of 186m below ground, is accessed via vertical shafts and has a capacity of 125 000m3 of gas, contained by a water curtain. The construction of the shafts and the cavern is described in detail in the paper.
Future issues of Energy will include papers on all aspects of energy supply and use. A special issue on the subject of low carbon buildings is planned for 2008. Download the call for papers at www.energy-ice.com.
