Tables of costs and specifications


What follows is a "core dump" of the spreadsheets that I am using to calculate heliostat costs and specifications. I am posting them to give people an idea of some of the design and cost factors under consideration. I have been promising certain people to show them some numbers and I felt it was taking too long to get everything pretty; at the very least I should show how far I've gotten.

I welcome comments and questions, but let's get a few things perfectly clear: the so-called "business plan" is just a few numbers I am tossing around - it is far from complete and it is missing some very important elements. This is a work in progress.

Now, with all of that out of the way, here is the main number that you want to know: the mini-heliostats will cost US$45.95/m2 (or Sfr68.87/m2) of reflective surface.


Overview

Conventional vs MiniHeliostat costs
Mini_heliostat costs
Business plan
RH1_0 specifications
Miscellaneous material costs
Mold costs
Gear pricing schemes
Gear train specs
RH0_1 specifications


Sheet 1: Conventional vs MiniHeliostat costs

Comparison of the costs of a 150m2 second generation stretched-membrane heliostat*, a 150m2 first generation-style glass mirror heliostat*, and 150m2 of Mini-Heliostats**
Stretched-Membrane First-Generation Mini-Heliostats Mini-Heliostats
($) ($/m2) ($) ($/m2) ($) ($/m2) (Sfr) (Sfr/m2)
Mirror Module and Support Structure 5,136.45 34.24 7,024.02 46.83 2,225.49 14.84 3,338.23 22.25
Materials 4,357.33 29.05 6,244.90 41.63 1,299.56 8.66 1,949.34 13.00
Labor 611.52 4.08 611.52 4.08 925.93 6.17 1,388.89 9.26
Equipment (including interest) 157.66 1.05 157.66 1.05 0.00 0.00 0.00 0.00
Consumables 9.94 0.07 9.94 0.07 0.00 0.00 0.00 0.00
Drive and Pedestal 2,067.00 13.78 2,067.00 13.78 3,204.73 21.36 4,807.09 32.05
Drive Assembly 1,694.00 11.29 1,694.00 11.29 1,132.56 7.55 1,698.84 11.33
Pedestal 266.00 1.77 266.00 1.77 1,527.78 10.19 2,291.67 15.28
Assembly Drive/Pedestal/Electric 107.00 0.71 107.00 0.71 544.39 3.63 816.58 5.44
Foundation 934.00 6.23 934.00 6.23 46.30 0.31 69.44 0.46
Labor (Field Site) 251.26 1.68 251.26 1.68 185.19 1.23 277.78 1.85
Buildings (Including Interest) 16.95 0.11 16.95 0.11 0.00 0.00 0.00 0.00
Field Wiring 434.00 2.89 434.00 2.89 77.78 0.52 116.67 0.78
Total Heliostat Cost 8,839.66 58.93 10,727.23 71.51 5,739.47 38.26 8,609.21 57.39
ROI and Taxes @ 20% 1,767.93 11.79 2,145.45 14.30 1,147.89 7.65 1,721.84 11.48
Selling Price (unadjusted for PPI) 10,607.59 70.72 12,872.68 85.82 6,887.37 45.92 10,331.05 68.87
Selling Price in 1996 US dollars 12,860.53 85.74 15,606.70 104.04 6,887.37 45.92 10,331.05 68.87
($) ($/m2) ($) ($/m2) ($) ($/m2) (Sfr) (Sfr/m2)
Stretched-Membrane First Generation Mini-Heliostats Mini-Heliostats
* The original costs were reported in 1988 US$. The following data were used to convert to 1996 values.
Dollar conversion factors between 1988 and 1996 accounting for 1988 and 1996 accounting for inflation of the cost of CAPITAL EQUIPMENT (1982=100, source:BCI)
Year Producer Price Index
1988 113
1996 137
RATIO: 1.21
** The Mini-Heliostat costs have been calculated in Swiss francs. Use the following conversion table.
Sfr to US$ conversion factor 0.67
US$ to Sfr conversion factor 1.50
*Source of data for stretched membrane costs:
"Improved Stretched Membrane Heliostat Mirror Module Development",
by K.J. Beninga, B.L. Butler, and J.A. Sandubrae
Science Applications International Corporation (SAIC)
10401 Roselle Street
San Diego, California 92121, USA
page 139, Table 4
Solar Thermal Technology - Research Development and Applications:
proceedings of the fourth (1988) international symposium
edited by B.P. Gupta
1990 Hemisphere
ISBN 1-56032-095-8

Sheet 2: Mini_heliostat costs

Mini-heliostats cost (Sfr) 150 m2 under consideration
for X square metres 0.54 m2/assembly
(Sfr) (Sfr/m2) (Sfr/assembly) % of total
Mirror Module(s) 3,338.23 22.25 12.02 32
Materials 1,949.34 13.00 7.02 19
Labor 1,388.89 9.26 5.00 13
Equipment (including interest) 0.00 0.00 0.00 0
Consumables 0.00 0.00 0.00 0
Drive and Pedestal/Support structure 4,807.09 32.05 17.31 47
Drive Assembly 1,698.84 11.33 6.12 16
Pedestal/Support structure 2,291.67 15.28 8.25 22
Assembly Drive/Pedestal/Electric 816.58 5.44 2.94 8
Foundation 69.44 0.46 0.25 1
Labor (Field Site) 277.78 1.85 1.00 3
Buildings (Including Interest) 0.00 0.00 0.00 0
Field Wiring 116.67 0.78 0.42 1
Total Heliostat Cost 8,609.21 57.39 30.99 83
ROI and Taxes @ 20% 1,721.84 11.48 6.20 17
100
Selling Price 10,331.05 68.87 37.19
(Sfr) (Sfr/m2) (Sfr/assembly) % of total

Sheet 3: Business plan

Rough estimates of pay-back time and income Scenario Descriptions
Worst Case Best Case Solar Electricity Value Conversion System
Pay-back time (heliostats only) years 8.09 0.65 Worst Case low (Swiss legal limit) low efficiency
Target gross annual income Sfr/year 50000.00 50000.00 Best Case high (incentive programs) high efficiency
Target gross annual income $/year 33333.33 33333.33
Cost of needed heliostats Sfr 404567.98 32365.44
Cost of needed heliostats $ 269711.99 21576.96
Cost of heliostats per unit area Sfr/m2 68.87 68.87
Cost of heliostats per unit area $/m2 45.92 45.92
Area of heliostats needed m2 5874.06 469.92
Income per square metre per year Sfr/m2year 8.51 106.40
Income per square metre per year $/m2year 5.67 70.93
Value of electricity Sfr/kWh 0.16 1.00
Value of electricity $/kWh 0.11 0.67
Direct sunshine kWh/m2year 700 700
Efficiency of engine & receiver 0.1 0.2
Efficiency of mirrors 0.8 0.8
Efficiency of generator 0.95 0.95
Efficiency of system 0.08 0.15
Peak direct insolation kW/m2 0.94 0.94
Peak thermal power kW 4413 353
Peak mechanical power kW 441 71
Peak electrical power kW 419 67
Sfr to US$ conversion ratio 0.667

Sheet 4: RH1_0 specifications

ITEM MATERIAL AMOUNT COST FRACTION
quantity unit Sfr/unit Sfr/assembly %
Total 0.54 m2 45.82 24.74 100.0
quantity unit Sfr/unit Sfr/assembly
Reflectors 6 1.17 7.02 28.4
mirror surface aluminum-coated mylar 0.09 m2 2.88 0.26
mirror backing PVC plaque, 1 mm thick 0.09 m2 9.78 0.88
mirror frame reflector part 1 0.03 0.03
LENGTH MIRROR 0.3 m
Reflector mounting and gear trains 6 1.02 6.12 24.7
azimuth gear train azimuth drive gear train 1 0.30 0.30
elevation gear train elevation drive gear train 1 0.57 0.57
inclination support reflector part 2 0.03 0.06
mirror support reflector part 2 0.03 0.06
reflector base reflector part 1 0.03 0.03
Support Structures 1 8.25 8.25 33.3
pipe with holes PVC electrical conduit 16 mm diameter 8.1 m 0.85 6.89
pipe T joints PVC T 16 mm diameter 2 0.10 0.20
pipe elbows PVC elbow 16 mm diameter 4 0.10 0.40
legs PVC electrical conduit 16 mm diameter 0.9 m 0.85 0.77
Wiring system 1 0.42 0.42 1.7
power line bare alu wire 0.4 m 0.10 0.04
signal line bare alu wire 0.4 m 0.10 0.04
ground line bare alu wire 0.4 m 0.10 0.04
power connector stainless 1 0.10 0.10
signal connector stainless 1 0.10 0.10
ground connector stainless 1 0.10 0.10
Drive system
common drive 1 1.30 1.30 5.3
toy DC motor steel, iron 1 0.50 0.50
coupling magnets iron 4 0.10 0.40
common drive gear train common drive gear train 1 0.40 0.40
selector drive 1 1.64 1.64 6.6
toy DC motor steel, iron 1 0.50 0.50
coupling magnets iron 4 0.10 0.40
selector gear train axis selector gear train 1 0.74 0.74
set of other pieces 1 5.07 5.07
mount recycled plastic 1 0.07 0.07
batteries NiH AA batteries 4 1.00 4.00
drive electronics 1 pole, double throw switches 2 0.25 0.50
hermetic case PVC electrical box 1 0.50 0.50

Sheet 5: Miscellaneous material costs

COST HARDWARE STORE WHOLESALERS
Material Sfr unit Sfr Sfr
ECP300 ? 16.00 m2 16.00 16.00
aluminum-coated mylar 2.88 m2 2.88 2.88
white plastic U profile 1.00 m 4.39 1.00
white plastic rectangle profile 3x10mm 0.45 m 2.45 0.45
white plastic rectangle profile 5x20mm 1.50 m 3.82 1.50
PVC plaque, 1 mm thick 9.78 m2 9.78
PVC electrical conduit 16 mm diameter 0.85 m 0.67 0.85
PVC elbow 16 mm diameter 0.10 each 0.78 0.10
PVC T 16 mm diameter 0.10 each 0.98 0.10
PVC bride 16 mm diameter 0.10 each 0.57 0.10
PVC rod, 3 mm diameter 0.11 m 0.11 0.11
screw/nut pairs 0.02 pair 0.10 0.02
glass mirror tile 20.00 m2 49.72 20.00
PVC electrical box 0.50 each 3.50 0.50
reduced motor 10.00 each 30.00 10.00
NiH AA batteries 1.00 each 4.00 1.00
1 pole, double throw switches 0.25 each 2.00 0.25
Specially fabricated parts
General estimation method:
reflector part 0.03 each
array part 0.07 each
Assemblies
common drive gear train 0.40 each
azimuth drive gear train 0.30 each
elevation drive gear train 0.57 each
axis selector gear train 0.74 each

Sheet 6: Mold costs

MOLD FOR REFLECTOR UNITS
Estimate of production mold Sfr 13000.00
Mirror area m2 5874
Number of reflectors 65267.34
Number of parts per reflector (estimate) 40
Cost to do one molding Sfr 1.00
Cost per part per molding Sfr 0.03
Fixed cost divided by number of parts Sfr 0.00
Total cost per reflector part Sfr 0.03
MOLD FOR ARRAYS
Estimate of production mold Sfr 11000.00
Mirror area m2 5874
Number of arrays 10877.89
Number of parts per array (estimate) 30
Cost to do one molding Sfr 1.00
Cost per part per molding Sfr 0.03
Fixed cost divided by number of parts Sfr 0.03
Total cost per array part Sfr 0.07

Sheet 7: Gear pricing schemes

Mädler - Norm Antrieb AG
rebate (%) 0 3 10 13 16 26 32 42
quantity 1 5 10 25 50 100 250 500 quantity
gear type teeth cost in Sfr 1996 teeth
spur, mod 0.5, acetal 12 0.31 0.30 0.28 0.27 0.26 0.23 0.21 0.18 12
EXTRUDED 20 0.52 0.40 0.31 20
0.52 0.50 0.47 0.45 0.44 0.39 0.35 0.30
120 2.50 1.88 1.48 120
2.50 2.42 2.26 2.18 2.10 1.85 1.69 1.45
conic, mod 0.5, acetal 16 0.40 0.33 0.28 16
MOLDED 0.40 0.39 0.36 0.35 0.34 0.30 0.27 0.23
conic, mod 1.0, acetal 15 1.21 1.00 0.82 15
MOLDED 1.21 1.17 1.09 1.05 1.01 0.90 0.82 0.70
45 3.67 3.04 2.50 45
3.67 3.55 3.31 3.20 3.08 2.72 2.49 2.13
quantity 1 5 10 25 50 100 250 500 quantity
log10 quantity 0 0.7 1 1.4 1.7 2 2.4 2.7
calc. rebate 3.29 6.41 8.54 12.48 16.63 22.16 32.38 43.14
diff^2 10.85 10.16 1.29 0.18 0.25 13.29 0.02 1.46 37.49
rebate exp. 0.41
rebate coef. 0.03
Alfred Güdel AG
rebate (%) 0 5 10 20
quantity 1 5 10 20 quantity
gear type teeth cost in Sfr 1996 teeth
spur, mod 0.5, acetal 12 0.30 12
MOLDED 0.30 0.29 0.27 0.24
20 0.40 20
0.40 0.38 0.36 0.32
120 1.60 120
1.60 1.52 1.44 1.28
conic, mod 0.5, acetal 16 0.43 16
MOLDED 0.43 0.40 0.38 0.34
conic, mod 1.0, acetal 15 0.78 15
MOLDED 0.78 0.74 0.70 0.62
45 2.33 45
2.33 2.21 2.09 1.86
quantity 1 5 10 20 quantity
Nozag AG
rebate (%) 0 4 8 12 16 20 24 80
quantity 1 5 10 25 50 100 200 3276800 quantity
gear type teeth cost in Sfr 1996 teeth
spur, mod 0.5, acetal 12 0.50 12
MOLDED 0.50 0.48 0.46 0.44 0.42 0.40 0.38 0.10
20 0.70 20
0.70 0.67 0.64 0.62 0.59 0.56 0.53 0.14
120 2.70 120
2.70 2.59 2.48 2.38 2.27 2.16 2.05 0.54
conic, mod 0.5, acetal 16 0.60 16
MOLDED 0.60 0.58 0.55 0.53 0.50 0.48 0.46 0.12
conic, mod 1.0, acetal 15 1.33 15
MOLDED 1.33 1.27 1.22 1.17 1.11 1.06 1.01 0.27
45 3.98 45
3.98 3.82 3.66 3.50 3.34 3.18 3.02 0.80
quantity 1 5 10 25 50 100 200 3276800 quantity

Sheet 8: Gear train specs

Miscellaneous specs
sun rotation rate (RPM) 0.0007
coasting time of motor (seconds) 0.5
adjustment cycle time (seconds) 0.523
reflector part Sfr 0.030
array part Sfr 0.067
number of reflector parts in gear trains 29
number of array parts in gear trains 17
Order teeth / threads reduction of pair cumulative reduction RPM # turns for 0.1° change # turns while coasting cost
common drive 0.40
motor shaft 0 1 1 2200 75 18.33
pinion 12 1 1 2200 75 18.33 0.067
magnet gear 120 10 10 220 7.5 1.83 0.067
"virtual" shaft 0 1 10 220 7.5 1.83
magnet wheel 0 1 10 220 7.5 1.83 0.067
shaft 0 1 10 220 7.5 1.83 0.067
pinion 12 1 10 220 7.5 1.83 0.067
main transmission gear 120 10 100 22 0.75 0.18 0.067
Order teeth / threads reduction of pair cumulative reduction RPM # turns for 0.1° change # turns while coasting cost
azimuth drive 0.30
main transmission gear 120 1 100 22 0.75 0.18
axis transmission gear 12 0.1 10 220 7.5 1.83 0.030
shaft 0 1 10 220 7.5 1.83 0.030
worm 1 1 10 220 7.5 1.83 0.030
wormgear 30 30 300 7 0.25 0.06 0.030
shaft 0 1 300 7 0.25 0.06 0.030
worm 1 1 300 7 0.25 0.06 0.030
wormgear 30 30 9000 0.2444 0.01 0 0.030
shaft 0 1 9000 0.2444 0.01 0 0.030
spur 20 1 9000 0.2444 0.01 0 0.030
az gear 600 30 270000 0.0081 0 0 0.030
azimuth 0 1 270000 0.0081 0 0
Order teeth / threads reduction of pair cumulative reduction RPM # turns for 0.1° change # turns while coasting cost
elevation drive 0.57
main transmission gear 120 1 100 22 0.75 0.18
axis transmission gear 12 0.1 10 220 7.5 1.83 0.030
shaft 0 1 10 220 7.5 1.83 0.030
worm 1 1 10 220 7.5 1.83 0.030
wormgear 30 30 300 7 0.25 0.06 0.030
shaft 0 1 300 7 0.25 0.06 0.030
miter 16 1 300 7 0.25 0.06 0.030
miter 16 1 300 7 0.25 0.06 0.030
shaft 0 1 300 7 0.25 0.06 0.030
miter 16 1 300 7 0.25 0.06 0.030
miter 16 1 300 7 0.25 0.06 0.030
shaft 0 1 300 7 0.25 0.06 0.030
miter 16 1 300 7 0.25 0.06 0.030
miter 16 1 300 7 0.25 0.06 0.030
shaft 0 1 300 7 0.25 0.06 0.030
worm 1 1 300 7 0.25 0.06 0.030
wormgear 30 30 9000 0.2444 0.01 0 0.030
shaft 0 1 9000 0.2444 0.01 0 0.030
spur 20 1 9000 0.2444 0.01 0 0.030
az gear 600 30 270000 0.0081 0 0 0.030
azimuth 0 1 270000 0.0081 0 0
Order teeth / threads reduction of pair cumulative reduction RPM # turns for 15° change # turns while coasting cost
axis selector 0.74
motor shaft 0 1 1 2200 37.5 18.33
pinion 12 1 1 2200 37.5 18.33 0.067
magnet gear 120 10 10 220 3.75 1.83 0.067
"virtual" shaft 0 1 10 220 3.75 1.83
magnet wheel 0 1 10 220 3.75 1.83 0.067
shaft 0 1 10 220 3.75 1.83 0.067
worm 1 1 10 220 3.75 1.83 0.067
wormgear 30 30 300 7 0.13 0.06 0.067
shaft 0 1 300 7 0.13 0.06 0.067
bevel 15 1 300 7 0.13 0.06 0.067
bevel 45 3 900 2.4444 0.04 0.02 0.067
shaft 0 1 900 2.4444 0.04 0.02 0.067
circular cam 0 1 900 2.4444 0.04 0.02 0.067

Sheet 9: RH0_1 specifications

ITEM MATERIAL AMOUNT COST
quantity unit SFr/unit SFr/assembly
Reflectors+Mounting+Support 0.09 m2 86.09 7.75
quantity unit SFr/unit SFr/assembly
Reflectors 1 2.40 2.40
mirror glass mirror tile 0.09 m2 20.00 1.80
mirror frame white plastic U profile 0.6 m 1.00 0.60
LENGTH MIRROR 0.3 m
Reflector mounting and gears 1 2.16 2.16
azimuthal ring gear PVC rod, 3 mm diameter 0.5 m 0.11 0.05
inclination ring gear PVC rod, 3 mm diameter 0.9 m 0.11 0.10
azimuthal worm gear nylon 1 0.03 0.03
inclination worm gear nylon 1 0.03 0.03
inclination gear train PVC rod, 3 mm diameter 0.5 m 0.11 0.05
azimuthal ring white plastic rectangle profile 3x10mm 1.1 m 0.45 0.50
inclination support white plastic U profile 0.37 m 1.00 0.37
mirror support white plastic U profile 0.77 m 1.00 0.77
fasteners screw/nut pairs 10 0.02 0.20
az. axis selector PVC rod, 3 mm diameter 0.3 m 0.11 0.03
inc. axis selector PVC rod, 3 mm diameter 0.3 m 0.11 0.03
Support Structures 1 3.18 3.18
pipe with holes PVC electrical conduit 16 mm diameter 1.35 m 0.85 1.15
pipe T joints PVC T 16 mm diameter 2 0.10 0.20
pipe elbows PVC elbow 16 mm diameter 4 0.10 0.40
fasteners screw/nut pairs 12 0.02 0.24
legs screw/nut pairs 4 0.10 0.40
reflector bases PVC bride 16 mm diameter 8 0.10 0.80
Wiring 0 0.42 0.00
power line bare alu wire 0.4 m 0.10 0.04
signal line bare alu wire 0.4 m 0.10 0.04
ground line bare alu wire 0.4 m 0.10 0.04
power connector stainless 1 0.10 0.10
signal connector stainless 1 0.10 0.10
ground connector stainless 1 0.10 0.10
Drive system 1 12.94 12.94
main drive 1 10.15 10.15
reduced DC motor reduced motor 1 10.00 10.00
coupling magnets iron 0 0.10 0.00
magnet mounts recycled plastic 0 0.07 0.00
mount white plastic rectangle profile 5x20mm 0.1 1.50 0.15
selector drive 0 0.97 0.00
DC motor steel, iron 1 0.50 0.50
coupling magnets iron 2 0.10 0.20
magnet mounts recycled plastic 2 0.07 0.13
"gap-tooth" cam hard plastic 1 0.07 0.07
worm gear hard plastic 1 0.07 0.07
other pieces
mount recycled plastic 0 0.07 0.00
batteries NiH AA batteries 4 1.00 4.00
drive electronics 1 pole, double throw switches 2 0.25 0.50
hermetic case PVC electrical box 1 0.50 0.50

--

NO ePATENTS
Erik Rossen <rossen@rossen.ch>
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Tel: +41 22 362 45 08
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Copyright © 2000 until the heat-death of the Universe (thanks, Mickey!), by Erik Rossen
Last modified: 2008-10-06T09:02:27+0200

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