1. Electricity production and consumption

3. Typical Domestic Electrical Load???
Typical Daily Domestic Demand Profile (

4. Conventional lighting
Typical Domestic Electrical Load
Typical Daily Domestic Demand Profile (
Average = c.12kWh/Day
Conventional lighting
Activity related load
Base load

5. Components of domestic electrical load
Base load
Alarm systems
Control systems
Fridge/freezers
Essential stand-by items
Telecomms
Clocks etc.,
Activity related loads
Radio/TV/HiFi
Small appliances
Washing machines
PC/Modem/Printer
Fans, Pumps, Activators Etc.,
Components of domestic electrical load
Excluding thermal loads
Mostly cold fill
Cooking
Kettle
Coffee Maker
Microwave
Oven/grill
Hobs
Lighting
After and before sunrise
Weekday
Weekend

6. High efficiency lighting
Cooking etc.,
Activity related load
Base load
High efficiency lighting

10. What to do with the surplus power?

11. 2007 ESB Night saver tariff (including VAT)

12. 49 kWh/m2/yr
Good match between PV surplus and thermal demand for > 25% of time

13. x 2.5/3.4

14. Financial and environmental performance

15. ESB plus gas plus PV gives lowest CO2 emission
Standing charge = 50% of total cost
ESB night saver plus PV gives lowest running cost

16. ESB Night Saver gives lowest running cost solution
Savings with PV = 2.5 x Savings with Solar Thermal
ESB plus Gas gives lowest CO2 emission solution
CO2 reductions with PV = 4 x CO2 reductions with Solar Thermal

17. Looking at electrical load in more detail
Fridge & Freezer c.40%
PC etc., > 15%
TV, VCR >15%
Base load c.15%

18. Essential services – on 24/7
Separate circuits
Heating and hot water
On during periods of solar surplus and at night time
Essential services – on 24/7
Security lighting
Alarm systems
Control systems
Fridge/freezers
Essential stand-by items
Telecomms
Clocks etc.,
Activity related – on when occupied
Lighting
Radio/TV/HiFi
Small appliances
PC/Modem/Printer
Fans, Pumps, Activators Etc.,
Other 24/7 loads
Cookers
Washing machines
VCR/DVD-HDD
Timer controlled devices
Possible daytime only operation
Schedule plus switches in bedroom and at entrance door

19. Load with controlled activity related circuit
Assuming 85% occupancy

20. Figures for controlled activity related circuit
plus PV
CO2 emissions down by 42%
Running costs down by 36%

21. As previous slide with heating load reduced by 50% through use of better insulation and heat recovery
CO2 emissions down by 62%
Running costs down by 50%

22. Good match between PV surplus and thermal demand for c.50% of time
33 kWh/m2/yr
Good match between PV surplus and thermal demand for c.50% of time

23. Water based heating systems
Standard system + PV compared with Biomass/DHS system
Standard system + PV
23% lower emissions
18% lower cost
Assuming biomass emissions = 10% natural gas

24. Lowest capital and running cost
Standard control and heat load
Cool Power control and reduced heat load
Lowest capital and running cost

25. ESB Urban Domestic plus Storage Heating ESB Night Saver
Lowest capital and running cost
ESB Urban Domestic plus Gas
ESB Night Saver plus PV
Lowest capital and running cost
ESB Urban Domestic plus Gas
plus PV
ESB Urban Domestic plus DHS
ESB Night Saver plus PV
Lowest capital and running cost
ESB, Gas plus PV
Lowest CO2
ESB Urban Domestic plus DHS
Optimised electrical loads plus reduced heat load