The Potential of Solar Energy in the UK
Cynthia SullivanFebruary 24th 2005
Introduction
• Greater potential than is believed
• Largely ignored in national energy policy
• The UK receives on average 950 kWh solar radiation per m2 p.a.
• Can be difficult and expensive to harness
• Can make contribution to our domestic energy needs
900
1000
1100
1200
Annual UK solar radiation kWh/m2
Background
• Diffuse and direct solar radiation
• 40% of the radiation received in Europe is diffuse
• UK solar energy systems utilise diffuse radiation on domestic scale
• Solar thermal, heat water
• Solar electric, creates electricity through photovoltaic conversion
Solar Thermal
• Solar collectors transform solar radiation into heat
• 40% of hot water needs, supported by a conventional water heating system
• South facing
• 2.5 m2 flat plate collector costs £3000
• Clear Skies grant of £400
Solar ThermalCurrent Situation
Active Solar Heat Generated 1990 - 2003 (PJ)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
Year
Hea
t G
ener
ated
(P
J)
• Since 1990 heat generated through active solar heating has increased
• Rate of growth increased since 1999• In 2003, 0.9 PJ of heat generated
Solar ThermalAssumptions
• Conventional 2.5 m2 flat plate collector
• 140 liters a day
• Temperature increase of 45 °C
• 40% of hot water needs
• Cost £3000
• Clear Skies grant to be improved to £800
• Number of suitable properties in 2000, 8,456,000
• Every suitable house built between now and 2030 to receive solar collector.
• All existing suitable houses to receive solar collector between now and 2030.
Solar ThermalProjections
YearHeat
Generated (PJ)
Existing Capacity (PJ)
Total Heat Capacity
(PJ)Cost
2000 3.256 0.4995 3.756 -
2005 3.376 0.891 4.267 £10,165,000,000
2010 3.511 - 4.402 £1,749,000,000
2015 3.645 - 4.536 £1,749,000,000
2020 3.765 - 4.656 £1,749,000,000
2025 3.884 - 4.775 £1,749,000,000
2030 4.004 - 4.895 £1,749,000,000
Expenditure £15,032,000,000
Budget £40,000,000,000
Remaining £24,968,000,000
Solar Electric
• Photovoltaic materials generate direct current electrical power when exposed to photons
• Provide all or some of electrical needs
• 80 kWh per m2
• Expensive, £8000 for 8m2
• Clear Skies grant of £4000
Solar ElectricCurrent SituationPV Electricity Generated 1990 - 2003 (PJ)
0
0.005
0.01
0.015
0.02
0.025
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
Year
Ele
ctr
icty
Ge
ne
rate
d (
PJ
)
• Developing technology• Rapid growth since 1998• In 2003, 0.02 PJ of electricity generated
Solar ElectricAssumptions
• 8m2 photovoltaic area
• 2.3 GJ per 8m2
• £8000
• Half price in 10 years
• Clear Skies grant to be increased to 75% of project cost
• Every suitable house built between now and 2030 to
receive 8m2 photovoltaic area
Solar ElectricProjections
YearElectricity Generated
(PJ)
Existing Capacity (PJ)
Total Electrical Capacity
(PJ)Cost
2000 0.004 0.0072 0.01 £930,000,000
2005 0.021 0.0216 0.043 £4,650,000,000
2010 0.042 - 0.063 £4,462,500,000
2015 0.062 - 0.083 £3,150,000,000
2020 0.080 - 0.101 £2,325,000,000
2025 0.097 - 0.119 £2,325,000,000
2030 0.115 - 0.137 £2,325,000,000
Expenditure £20,167,500,000
Budget £40,000,000,000
Remaining £19,832,5000
Summary
Thermal• 4.895 PJ by 2030• Cost £15,032,000,000
Electric• 0.137 PJ by 2030• Cost £20,167,500,000
Combined• 5.095 PJ by 2030• Cost £35,199,500,000
Should we invest in solar thermal, solar electric, or both?