Sydney Lenssen's supposition (NCE 24 September) is entirely correct -Dinorwig pumped storage scheme is indeed still an engineering triumph of note.
Certainly First Hydro's 65,000 visitors a year to the station complex seem to find it so. This year they included ICE's Power Board, the British Dam Society's 10th conference and innumerable engineering students and overseas specialists.
As Dinorwig approaches 15 years of virtually continuous operation and availability, its six 300MW pump turbines are busier than ever, providing not only the services originally designed for but others which technological developments, many achieved after substantial research and development by
First Hydro, make available.
These enhanced services support the National Grid and other generators in meeting efficiently the distinct but ever changing instantaneous consumption demands of electricity consumers in England and Wales. Grid security has been top priority throughout and has been achieved despite some very testing times.
First Hydro is however confident it will meet and overcome the challenges and uncertainties of the future, including current reviews of the industry, its market and its regulation in the same old ways: engineering, investment, flexibility and rapid response, all on the basis of a small but well motivated and rewarded workforce from a community which shares in the rewards of success.
In 1999 Dinorwig will reach 25 years since 'cutting-the-turf' and First Hydro hopes that many friends and long standing contributors to the achievement will return to visit.
The explanation of the comments made in the DTI review of energy resources is very simple. Merz & McLellan described a very narrow view of grid support services which gave the impression, falsely,
that only two units were available for grid support.
In fact all six units are regularly available for system support using Dinorwig's phenomenally fast response. On the basis that a picture saves a thousand words, the diagram below gives a very recent example of exactly that.
Sorry Sydney, to spoil a good story with the facts.
Owen P Williams (M), First Hydro, Dinorwig power station, Llanberis, Gwynedd LL55 4TY.