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?