The integrated Severn barrage complex: Harnessing tidal, wave and wind power

The integrated Severn barrage scheme could provide more than 8% of the current electricity requirements of England and Wales. The project would be well within the limits of current technology, cost slightly in excess of £1010, with a construction period approaching 10 years. Electricity could be generated from the tidal aspect of the scheme at 6·0 p/kWh at an 8% discount rate taken over the 120 year technical lifetime of the system (or ∼8·3 p/kWh at an 11% discount rate taken over a 40 year period). Electricity derived from the wind and wave energy harnessing-systems could be generated at between 4·4 and 8·8 p/kWh at an 11% discount rate over the 25 year lifetime of the systems. The simple pay-backs of the various schemes are wind ∼7 years; wave ∼10 years; and tidal ∼14 years, i.e. all well within the respective economic lifetimes of the systems. The inclusion of a public road along the top of the barrage would not only prove a national asset but also a source of income. There are numerous additional regional/national benefits (e.g. increased tourism, flood protection, additional employment, improved economy, etc.) associated with the construction and running of the barrage that should be considered when determining what Government assistance should be provided to encourage private financial investment in this desirable part of our national infrastructure. Once constructed, the barrage would be generating cheap, clean electricity for most of the next century.