16469- Low Energy Building Design

Presentation 2- Supply Options

Edmund TsangGraham DowMarc Smeed

Goals for our Power Supply

•Environmental•Financial•Operational

Environmental

• Low Co2 and other greenhouse gas emissions

• Low embodied energy• Sustainable

Operational

• Operable by non-technical personnel or autonomous operation

• Maintenance commitments must not be time consuming or expensive

• Demand/comfort conditions must be met at all times

• Should be efficient• Must be reliable

Initial Rationalisations

• Infeasible designs:

– Large Scale Wind– Biomass– Hydro Power

Available Technology• B+Q sell a windsave

turbine £1500 • Rated Power Output:

1kW @ rated wind speed

• Rated Wind Speed: 12.5m/s

• Cut-in Wind Speed: 3.5 to 5 m/s @ hub height

• Cut-out Wind Speed: 14 m/s@ hub height

Available TechnologyProven Stewarton based company

Wind Turbine System Basic cost (Excludes foundation work)

WT 600 £8,000

WT 2500 £10,900

WT 6000 £18,200

WT 15000 £39,000

Wind Data Glasgow  Wind at 10 m Wind at 10m

Month [knots] [m/s]

Jan 6.9 3.55

Feb 6.9 3.55

Mar 6.8 3.50

Apr 6 3.09

May 5.4 2.78

Jun 5.5 2.83

Jul 5.2 2.68

Aug 5.1 2.62

Sep 6.1 3.14

Oct 6.2 3.19

Year 6.1 3.14

From Paisley weather station 32m above sea level 1971-2000 averages.

Day 80- March 21

-40.00

-30.00

-20.00

-10.00

0.00

10.00

20.00

30.00

40.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hour

Alti

tude

(D

egre

es)

Altitude

0.00

1.00

2.00

3.00

4.00

5.00

6.00

1 92 183 274 365

Day of the Year

Sol

ar R

esou

rce

(kW

h/m

2)

Series1

Average Beam Intensity

0.00

20.00

40.00

60.00

80.00

100.00

120.00

140.00

160.00

1 92 183 274 365

Day of the Year

Bea

m I

nten

sity

(W

/m2K

)

Mean Beam Intensity

Average Diffuse Intensity

0

20

40

60

80

100

120

140

1 92 183 274 365

Day of the Year

Inte

nsity

(W

/m2K

)

Mean Diffuse Intensity

Day 80- March 21

-20.00

0.00

20.00

40.00

60.00

80.00

100.00

120.00

140.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hour

Inte

nsity

@ C

olle

ctor

Sur

face

(W

/m2K

)Solar Intensity

Declination

-30.00

-20.00

-10.00

0.00

10.00

20.00

30.00

1 92 183 274 365

Day of the Year

Angl

e (D

egre

es)

Declination

Solar Potential?Solar Collector facing SW @ 60°

Assessment Methodology Assessment Element

Solar Thermal CHP (Gas) Biogas Micro-Wind PV GSHP

GHG Emissions No emissions at point of use

Relatively High Levels of emissions

  Relatively High Levels of

emissions

Zero Zero No emissions at point of use

Sustainable As long as the sun shines!

Can't run when the NG runs out

 As long as there are

plants and people

As long as the wind blows!

As long as the sun shines!

As long as there is a force to run the

motor

Capital Costs 6001 £/kWth 22723 £/kWe (1000 £/kWth)

 More than CHP gas.

15001 £/kWe 30002 £/kWe 800-14004 £/kWth

p/kWh zero 5.068  N/A zero zero 4.2 

Meeting Demand

Cannot be predicted or relied

upon

Can be ramped up to provide all

energy needs

Limited by the amount of 'Night Soil'

that is available

Cannot be predicted or relied

upon

Cannot be predicted or relied upon

Can be ramped up and down to meet

demand

Efficiency Energy Factor 2-39 85%3 85%3 30-60% 4-20% (Typical 12%)

COP 2.5-4

Compatibility w Fuel Cell CHP

Good because it produces thermal

energy

Good- it produces higher

levels of thermal than

electrical

Good- it produces

higher levels of thermal

than electrical

Not so good, because produces electricity- which is less useful than

heat.

Not so good, because produces electricity- which is less useful than

heat.

Good- it can use electricity for heating and

cooling.

Contextual Feasibility

 Good  Reasonably good

Poor Poor Fair Fairly

Assessment Methodology

Assessment Element Weighting Solar

ThermalCHP (Gas) Biogas

Micro-Wind

PV GSHP

GHG Emissions 5 + D 0 + + +

Sustainable 4 + A + + + +

Capital Costs 4 + T  - - - 0

p/kWh 5 + U 0 + + +

Meeting Demand 4 - M  0 - - +

Efficiency 2 - 0 - - +

Compatibility w CHP 4 -   0 - - +

Contextual Feasibility 7 +  - - + -

SUM Σ   15 0 -7 -7 7 17

Conclusions

Based on the criteria we established

Discounted Possible Definite

•Micro Wind •GSHP

•PV

•Solar Thermal

•Hydrogen CHP

List of References1 www.diy.com (B&Q Website)

2 Presentation- ‘Photovoltaics’ Dr N J Kelly

3 Dow’s CHP thing

4 www.saveenergy.org

5 www.theenergyguy.com/lifecyclecost.html

6 www.esru.strath.ac.uk/EandE/Web_sites/00-01/fuel_cells/chp.html

7 www.actionrenewables.org

8 www.hydro.co.uk

9 www.est.org.uk/myhome/generating/types/solarwater/

10

11

12

13

14

15