1. Hydro Power – the history and the future. Robyn Hammond, School of Environmental Sciences, University of East Anglia. 24 th February 2005

2. Background Hydro, or HEP (hydroelectric power) schemes have existed for many years, and the technology is well-established Hydro, or HEP (hydroelectric power) schemes have existed for many years, and the technology is well-established –Norway has used hydro power since the 1900s –UK has used large-scale hydro since 1950s and 1960s Hydro power qualifies for a Renewables Obligation Certificate according to the UK government Hydro power qualifies for a Renewables Obligation Certificate according to the UK government

3. Value Hydro power is used to generate electricity, not for heat generation Hydro power is used to generate electricity, not for heat generation It is very reliable, especially in pumped storage schemes such as Dinorwic It is very reliable, especially in pumped storage schemes such as Dinorwic It can come online in several seconds at peak demand times and may be ‘switched off’ as easily It can come online in several seconds at peak demand times and may be ‘switched off’ as easily

4. Limitations It is difficult to gain substantial energy from a flowing river – dams are constructed to harness maximum energy It is difficult to gain substantial energy from a flowing river – dams are constructed to harness maximum energy Capacity could only potentially be 2-3 times larger than present UK schemes Capacity could only potentially be 2-3 times larger than present UK schemes Pumped storage schemes use energy pumping water up to the top reservoir Pumped storage schemes use energy pumping water up to the top reservoir

5. Options Pumped storage e.g. Dinorwic, N. Wales Pumped storage e.g. Dinorwic, N. Wales Damming rivers e.g. small scale schemes in the Scottish Highlands Damming rivers e.g. small scale schemes in the Scottish Highlands

6. Electricity generation At present, hydro power accounts for approximately 2% of the UK electricity generation. At present, hydro power accounts for approximately 2% of the UK electricity generation. It is unlikely to increase much more because of limited resources and relative inefficiency – a maximum load factor of 40% It is unlikely to increase much more because of limited resources and relative inefficiency – a maximum load factor of 40%

7. Capacity for generation Capacity for generation according to hydro power installations in the UK

8. Real capacity including load factor Capacity for generation according to hydro power installations in the UK, accounting for load factor of 33% (mean load factor of present installations)

9. Inequalities Uneven balance between areas of high hydro generation and areas with high power usage Uneven balance between areas of high hydro generation and areas with high power usage –Increase transmission losses when available nationally –More efficient to supply locally, but lower demand

10. The Future As seen, production and capacity have stayed level or decreased slightly over recent years As seen, production and capacity have stayed level or decreased slightly over recent years –Other renewables more suitable, higher load factor –Limited by resource availability

11. Predictions Will not increase dramatically, as there are more efficient ways of producing energy Will not increase dramatically, as there are more efficient ways of producing energy –Qualifies as a renewable source so may increase slightly until other technology improves Will still be used for immediate energy in times of peak demand Will still be used for immediate energy in times of peak demand

12. Notes It is unlikely that any more large scale hydro schemes will be implemented in the UK, as most of the available suitable sites are in use It is unlikely that any more large scale hydro schemes will be implemented in the UK, as most of the available suitable sites are in use Small-scale hydro schemes may be implemented on a local scale, and these will make up the majority of the predicted power generation Small-scale hydro schemes may be implemented on a local scale, and these will make up the majority of the predicted power generation

13. Electricity generation in the future In 2003, 3228 GWh or 0.897 PJ were generated using hydro power, a decrease from 5335 GWh (1.482 PJ) in 1999. It is predicted by the government that UK energy generation from renewable resources in 2010 will be 10.83 PJ (39 TWh), and in 2015 and 2020 it will rise to 16.11 PJ (58 TWh)

14. Projections 2005 – up to 1.2 PJ (minimum 0.8 PJ) 2005 – up to 1.2 PJ (minimum 0.8 PJ) 2010 – up to 1.5 PJ (minimum 1PJ) 2010 – up to 1.5 PJ (minimum 1PJ) 2015 – up to 1.7 PJ (minimum 1.2 PJ) 2015 – up to 1.7 PJ (minimum 1.2 PJ) 2020 – up to 2 PJ (minimum 1.5 PJ) 2020 – up to 2 PJ (minimum 1.5 PJ) 2025 – up to 2 PJ (minimum 1.5 PJ) 2025 – up to 2 PJ (minimum 1.5 PJ) –The basis for these projections is that small-scale HEP schemes will become more popular in the future of electricity generation, and these amounts will be generated in this way