|
TDV has the potential to save about half the fan or
ventilation energy, as compared to a basecase system and about 2/3 of the
cooling energy. The technology would have little impact on heating, lighting or
other end uses. On a per square foot basis, this translates to a potential
savings of about 0.87 kWh/ft²-y. Demand savings are also significant with a
potential reduction of about 0.49 W/ft². Table
2summarizes energy and demand savings potential for each component of energy
use.
Table 2 – DV Energy and Demand Savings Potential
|
Electricity Use (kWh/ft²-y)
|
Peak Electricity (W/ft²)
|
|
End Use
|
Basecase
|
DV
|
Savings
|
Basecase
|
DV
|
Savings
|
|
Ventilation
|
0.76
|
0.38
|
0.38
|
0.17
|
0.09
|
0.09
|
|
Cooling
|
0.74
|
0.25
|
0.49
|
0.61
|
0.20
|
0.41
|
|
Heating
|
0.24
|
0.24
|
-
|
-
|
-
|
-
|
|
Indoor Lighting
|
2.95
|
2.95
|
-
|
0.57
|
0.57
|
-
|
|
Office Equipment
|
0.07
|
0.07
|
-
|
0.01
|
0.01
|
-
|
|
Outdoor Lighitng
|
0.81
|
0.81
|
-
|
-
|
-
|
-
|
|
Cooking
|
0.06
|
0.06
|
-
|
-
|
-
|
-
|
|
Refrigeration
|
0.12
|
0.12
|
-
|
0.02
|
0.02
|
-
|
|
Water Heating
|
0.17
|
0.17
|
-
|
-
|
-
|
-
|
|
Miscellaneous
|
0.47
|
0.47
|
-
|
0.07
|
0.07
|
-
|
|
Total
|
6.39
|
5.52
|
0.87
|
1.45
|
0.96
|
0.49
|
The state architect estimates that California will spend between $50 and
$75 billion on K-12 schools in the next 5 to 7 years. This money will be
used for a combination of new buildings and modernizations of existing
buildings. It is estimated that about 40% will go to new construction,
15% for HVAC modernizations (air conditioning buildings that are not now
air conditioned) and 45% will go for other modernizations. These data are
summarized in Table
3 along with typical construction costs. An estimate of
construction costs are needed to translate the expected expenditures to square
feet of new buildings and renovations.
Table 3 – Construction Costs
|
|
|
Const Cost ($/ft²)
|
Land Cost ($/ft²)
|
Soft Cost ($/ft²)
|
Total Cost
|
|
New Construction
|
40%
|
160
|
70
|
64
|
294
|
|
HVAC Modernization
|
15%
|
25
|
0
|
10
|
35
|
|
Other Modernization
|
45%
|
n. a.
|
n. a.
|
n. a.
|
0
|
|
Total
|
100%
|
n. a.
|
n. a.
|
n. a.
|
n. a.
|
Combining the data from Table 3 with the estimate of construction volume,California
is likely to build between 68 and 102 million ft² of new schools in the
next 5 to 7 years and between 214 and 321 million ft² of existing buildings
are likely to have their HVAC systems modified or replaced. This translates
to between 680 and 1,000 new schools based on school typical size. See
Table 4 for details.
Table 4 – Volume of School Construction Expected for the Next 5-7 Years
|
Low
|
High
|
|
Anticipated Construction Volume in $ (next 5-7 years)
|
50,000,000,000
|
75,000,000,000
|
|
New Construction (ft²)
|
68,027,211
|
102,040,816
|
|
HVAC Modernization (ft²)
|
214,285,714
|
321,428,571
|
Using the low side of the construction estimates ($50 billion) and combining
this data with the savings estimates from Table 2, an estimate can be generated
of the energy and demand savings potential related to the school construction
boom.
Table 5 has these data for varying levels
of DV saturation. The 100% column assumes
that all schools would incorporate the technology,
etc. Since it will be difficult to affect
much construction volume already in the pipeline,
an estimate based on a low saturation is
more reasonable. If we are able to affect
20% of the construction, this would result
in 49 GWh of electricity energy savings and
28 MW of peak demand reduction. Table 5 shows the savings for other saturation levels.
Table 5 – Estimate of State Wide Savings (for 5-7 year period)
|
|
Saturation of DV Technology
|
|
|
20%
|
40%
|
60%
|
80%
|
100%
|
|
Electricity
Savings
|
New
|
12
|
24
|
36
|
48
|
59
|
|
GWh
|
Modernization
|
37
|
75
|
112
|
150
|
187
|
|
Total
|
49
|
99
|
148
|
197
|
247
|
|
Peak Savings
|
New
|
7
|
13
|
20
|
27
|
33
|
|
MW
|
Modernization
|
21
|
42
|
63
|
84
|
105
|
|
Total
|
28
|
56
|
83
|
111
|
139
|
|
|
