Wind Energy And The Environment

Worldwide interest in wind energy has been growing over a number of years. We describe UK wind energy activities with particular reference to the Department of Energy's programme and survey progress with large wind turbines overseas. We review the results of assessment studies which show that wind energy has the potential for supplying a significant proportion of the nation's electricity needs, at a cost which at the lower end of the estimates could probably compete with other conventionl sources. Significant exploitation of the wind energy resource would require large numbers of machines and it is uncertain whether such numbers would in practice turn out to be environmentally acceptable. Factors which will influence this will include (not necessarily in order of importance) visual acceptability and land use restrictions, ecological impacts, electro-magnetic interference, noise and safety. We review each of these aspects and conclude that for land based wind turbines the major impacts are visual intrusiveness, electromagnetic interference (particularly TV interference) and noise. These factors could be significant at all sites, other effects are likely to be site-specific. There are a wide range of pre-existing activities and interests which may impose constraints on the location of wind turbine arrays offshore. Nevertheless when allowance is made for these, the remaining resource is comparable with total UK electricity demand and the size of the available resource need not ·be a constraint on interest in offshore wind power

Xist regulation and function eXplored

X chromosome inactivation (XCI) is a process in mammals that ensures equal transcript levels between males and females by genetic inactivation of one of the two X chromosomes in females. Central to XCI is the long non-coding RNA Xist, which is highly and specifically expressed from the inactive X chromosome. Xist covers the X chromosome in cis and triggers genetic silencing, but its working mechanism remains elusive. Here, we review current knowledge about Xist regulation, structure, function and conservation and speculate on possible mechanisms by which its action is restricted in cis. We also discuss dosage compensation mechanisms other than XCI and how knowledge from invertebrate species may help to provide a better understanding of the mechanisms of mammalian XCI

The Economic Analysis Of Wave Energy

The economic analysis of the production of electricity on a significant national scale from wave energy reported in ETSU's Strategic Review of the Renewable Energy Technologies showed that in 1982 it was una ttractive when compared with compet ing technol ogies , Subsequent analysis has refined our under standing of wave energy ecor, omics while confirming the findings of the Strategic Review. The Harwell electricity supply system model has been used to recalculate breakeven costs, net present values and benefit/cost rat ios in the s ame scenarios as used in the Strategic Review. Attention was focused on a 2 G1~ wave power station with an assumed annual l oad factor of 25% instal led between 2001 and 2010 with a life of 25 years. ~uch of t he analysis was carried out for this first wave ?Ower stati on but the sensitivities to the main assumptions and the economics of subsequent wave power stations ~ere considered. This mo re recent economic analysis shows that while wave energy can appear cost-effective under particularly favourable scenarios u sing optimistic assum p tions on costs a nd productivity, its overall economic prospects a re not go od. The analysis ~erely serves to strengthen the conclusion of the Strate g ic Review of the Renewable Energy Technologies that the economic prospects of wave energy are poor both in comparison with othe r renewable energ y technologies a nd with conventional thermal plant. This suggest s tha t wave powe r is only likely to be considered by a UK electricity board as som e form o f s trategic opti on which cou ld be relie d upon if other more ec onor:ii cally att ractive generation options became unavailable fo r non-economic reasons. Its deploynent would increase costs to the consumer in a ll scenarios considered