1. Presented by: Leo Menzinger
M.O.S.S.
T4.5 Solar energy potential
assessment

2. Outline
• Solar energy potential assessment
– Requirements
– System architecture
– Calculation
– Assessment and reporting
• Heat dispersion

3. Solar energy potential assessment
Requirements
Roof information
• Area
• Orientation
Solar irradiation
Additional information to
• Panel
• Costs
• Energy consumption

4. Calculate continuous roof areas
1. Identify geometry of all roof segments
CityGML ≤ LoD 2 + BoundedBy(Roof)
2. Generation of continuous roof areas
Identify planar roof structures
(e.g. excluding dormer of roofs)
 Parameter: tolerance (e.g.:  =3-5°)
3. Calculate roof area (m2)
Filtering of roof areas
 Parameter: Minimal roof area (e.g.: 5 m2)

Combining roof areas

5. Solar irradiation - dependency from roof
n: Dachfläche-Normalvektor
(senkrecht auf die Dachfläche)
d: Sonnenstrahl-Richtung
φSolDiff = 30?
φSolDiff = 0?
(volle Bestrahlung)
φSolDiff = 45?
φSolDiff = 90?
(verschattet)
φSolDiff > 90?
(verschattet)
Dachfläche-Neigung
(im Beispiel: 45?)
φSolDiff :
Winkel zwischen dem
Dachflächenormal und der
Sonnenstrahlrichtung
100%
50%
ca. 67%
0%
0%
Farbkodierung (Dach)
warm:
geeignet
kalt, verschattet:
ungeeignet
d
d
d
d
d
n
n
n
n

6. Solar potential assessment – system architecture
solar potential assessment service
3D City DB
request
r.sun
Irradiation
calculation
Parameter
/ settings
Yield
Area
….
Solar potential
calculation

7. Solar potential assessment – system architecture
solar potential assessment service
Irradiation
calculation
Parameter
/settings
Solar potential
calculation
Solar potential assessment service
Irradiation calculation (IND)
• Precondition for solar potential calculation
• Pprecalculation on monthly base (Performance reasons)
• Calculation settings
Solar energy potential calculation (MOSS)
• requires irradiation calculation
• Building ID
• assessment settings

8. irradiation calculation
irradiation calculation service
3D CityDatabase
r.sun
Precalculated
irradiation

9. irradiation calculation - R.SUN
GRASS GIS - R.SUN
(Geographic Resources Analysis Support System)
Free open source geographical information system
R.SUN
Computes solar irradiation raster maps for given day,
latitude, surface and atmospheric conditions.
The shadowing effect of the topography is optionally
incorporated.
 Result - irradiation raster map
[Wh/ m² * period]
Computing of electrical power

10. irradiation calculation – Influencing factors
GRASS GIS - R.SUN
Influencing factors
• Inclination and orientation of roof
• Atmospheric conditions
 direct (beam)
 diffuse
 reflected

11. irradiation calculation– Influencing factors
Influencing factors
• Geographical position
• Period of evaluation
 Principally free
 Statistical evaluation
 Hours of sun/day depends on
season
GRASS GIS - R.SUN

12. Solar energy potential assessment
solar potential assessment service
3D City database
request
Precalculated
irradiation
Buildings
roofs
Yield
Area
….
Parameter /
settings
calculation algorithm

13. Solar energy potential assessment - prototype
Demo

14. Evaluation and reporting
Energy yield
• Solar irradiation (precalculated)
• Total panel area
• Panel efficiency
• Energy loss in transmission

15. Evaluation and reporting
Costs
• Total area of panels (m2)
• Price of solar panels
• Costs of installation
• Costs for additional equipement
• Costs for operating the plant

16. Evaluation and reporting
Reduction of costs
Return of investment
• Averaged energy costs (actual)
• Actual energy consumption
• Feed-in tariff

17. Evaluation and reporting
Carbon savings / year
• Actual CO2 emission in energy
production (energy sources)

18. heat dispersion
infra-red areal surveys
Partner: Geofoto LLC, Zagreb
Heat loss from roofs (GEOF)
Temperature
• min
• max

19. Heat loss from walls
heat dispersion
Offer from T4.1:
Texturing via - novaFACTORY import
- SketchUp

20. Thank you for your attention
Contact details
Leo Menzinger
M.O.S.S. - lmenzinger@moss.de