1. SOLAR THERMAL WATER HEATING
SIMON WHELAN

2. Solar Thermal Water Heating
Topics
Solar Thermal Water Heating
Types of panels
Flat plates
Vacuum tubes
Cylinders
Cost/Payback

3. Solar Water Heating- uses
Domestic water heating
- High grade heat from the sun
- Mostly showers and washing
Dishwashers, washing machine often heated separately – need direct hot feed appliances
Space Heating Support
Large capital and material investment
Most energy in Summer when needed least
Better bang for heating buck in insulation and design

4. Water heating - % of your energy use

5. How do solar panels work 3 energy flows - heat collection, heat loss, heat transfer

6. Domestic Solar Water Heating
A. Solar panels
B. Pump Station
C. Cylinder
D. Boiler

7. 4 main things to consider
1.Orientation
South is best,
Anywhere between SW – SE OK
East West requires specific system
2. Occupancy = Water Usage =Size of Cylinder
L of hot water per person a day
3. Type of Panel – Flat Plate or evacuated tube
4. Size of Array

8. Two main Types of Panel;
Flat plate panels
-In Roof
-On Roof
Vacuum tube
-direct contact water heating
-Single-walled vacuum tube with heat pipes
-Twin-walled vacuum tube with heat pipe

9. Flat Panel – In roof - Galway

10. Flat Panel – In roof - Celbridge
Flashing to weather proof
Very Similar to Velux Windows 10

11. Flat Panel – In roof - Celbridge
Install roof covering (slates/Tiles) around flashing
No wind load issues
Pipework runs directly in to the attic space – no roof penetration issues 11

12. Flat Panel – on roof 2 fixing options - Bolts – Slate roof - Bracket – Tile roof12

13. Flat Panel – on roof - Delgany
Use of brackets on tile roof
Alumium Profile to support panels 13

14. Advantages of Flat plates
Durable option – long life time years
Better Aesthetics – great looking panel flashed into roof
Can take up less surface area on roof than evacuated tubes

15. Vaccuum tubes: Bray 15

16. Vaccuum tubes –Heat pipes

17. Frame on roof contains tubes – mutiple panels in series
Multiple panels in in Bray- straight connection. 17

18. Flat roof:
Watch the wind load 18

19. Ground mount:
Long Pipe Run – inefficiencies introduced 19

20. Typically more efficient than FP per m2 of Aperture area
ADVANTAGES OF TUBES
Typically more efficient than FP per m2 of Aperture area
Totally insulated – no heat loss
Passively tracking – Incident Angle Modifier
Lower thermal mass
Lighter to lift into place
Sit on top of slates – easier to retrofit
Double wall vacuum tubes are potentially a very sustainable product in Ireland.
DISADVANTAGES
Aesthetics
Maintenance required after 15 to 20 yrs but modular

21. Pump station installation
Attic installation Controller in accessible position Expansion Vessel installed below pipe line Blow off vessel 3 port valve (HT) to heat dump Need power point – fused circuit in area. 21

22. Solar Controller: Resol BS3
Temperature displays
Controls Pump
Frost-protection
Store temperature limitation
Excess heat dissipation to radiator or can be after heat function 22

23. Solar Cylinders Dual/Triple coil Cylinders
Tall = better stratification
Insulation thickness 50mm min
Copper or Stainless steel
High efficiency solar coil - 20% of panel surface area
Two sensor ports for controller temperature probes
Consider weight of larger cylinder!

24. Choosing a System – Look for Energy yield not Efficiency
Sun is a moving energy source.
Panels differ
Zero loss efficiency describes efficiency at normal incidence - Noon
Not sufficient to describe performance accurately.

25. Choosing a System – Look for Energy yield not Efficiency
Incident Angle Modifier
Energy yield of system
Not efficiency of panel
TSol/DEAP/Test results
Establish Cost/Benefit

26. Costs and Payback How long is a piece of string?
Typical cost range from E4500 – E5500 installed
Grant aid brings cost to 3500 – 4000
Change in subsidy structure is forecast
Many variables: level of water use
Cost/type of primary heating
Durability of solar system – long term
Future energy costs
At today’s prices solar can contribute approx Euro200 – 300 per annum.
Hartwick Rule: Invest profits from natural resource use in technological replacements 26

27. Commercial Installations: Hotels/B&B’S – solar makes a lot of sense Old Rectory Kinsale:

28. Tesco – large daytime occupancy:

29. Further information:
Thank You!