County of San Diego 2005/2006 Greenhouse Gas Emissions Inventory

estimated electricity consumption and costs associated with the activities that generated these emissions. The
County spent approximately $1.3 million in 2006 on the electricity that was the cause of these emissions.
Table 3.4: Energy Use and Emissions from Public Lighting
Greenhouse Gas
Source
Emissions
(metric tons CO 2 e)
Percent Emissions
of All Lighting
Electricity Use
(kWh) Cost
Streetlights 1,741 81% 4,891,517 $1,133,645
Traffic Signals/ Controllers 348 16% 978,277 $150,343
Park and Other Outdoor Lighting 57 3% 160,375 $29,903
TOTAL 2,147 100% 6,030,169 $1,313,891
3.4.3 Water Transport
This section addresses any equipment used for the distribution of water and stormwater. 9 Typical systems included
in this section are water pumps/lifts, sprinklers, and other irrigation controls. 10 The County of San Diego operates a
range of water transport equipment, including transport of wastewater to the County’s treatment facilities.
In 2006, the operation of the County’s water transport equipment produced approximately 78 metric tons of CO 2 e
from the above sources. Table 3.6 depicts 2006 emissions per equipment type and shows estimated activities and
costs associated with the operation of this equipment. The County of San Diego spent approximately $30,000 in
2006 on the electricity that was the cause of these emissions.
Table 3.5: Energy Use and Emissions from Water Transport Equipment
Source
Greenhouse Gas
Emissions (metric
tons CO 2 e)
Percent Emissions of
Water Transport
Equipment
Electricity
Use (kWh)
Cost
($)
Water Pumps 75 96% 210,979 $29,079
Irrigation / Sprinkler Systems 3 4% 9,002 $1,218
TOTAL 78 100% 219,981 $30,297
3.4.4 Wastewater Treatment Facilities
Wastewater coming from homes and businesses is rich in organic matter and has a high concentration of nitrogen
and carbon (along with other organic elements). As wastewater is collected, treated, and discharged, chemical
processes can lead to the creation and emission of two greenhouse gases: methane and nitrous oxide. Local
9 While equipment that transports water and stormwater may be managed separately in the County’s operations, the types of equipment are
similar, and therefore the ways to reduce emissions from this equipment are similar. For this reason, this section groups equipment used for
transporting water and wastewater.
10 This section does not include emissions from decomposition or processing of wastewater in wastewater treatment facilities. These
emissions are included in Section 3.4.4.
2005/2006 San Diego County Greenhouse Gas Emissions Inventory 23