31-10-2012, 03:42 PM
ENERGY CONSERVATION
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Energy Conservation
Recently there has been wide-spread public and official concern about energy supplies, both
present and future. The fundamental problems underlying the projected decreasing supply of
traditional energy sources are of national or statewide scope, but there are significant
contributions which can be made by local government. Land use patterns, air quality programs,
growth policy, transportation, and residential densities all directly affect local energy
consumption. Conservation of existing energy, both by City actions and by all City residents, is
also within the scope of local government. Alternative energy sources, to provide for at least
part of the City's needs, can be investigated and developed. Since unlimited supply and
availability can no longer be taken for granted, energy considerations now need to be evaluated
along with the other factors that enter into the formulation of City policies and decisions.
FINDINGS
Supply and Demand
Before the 1973 "energy crisis,” the annual growth rate of San Diego's energy use was nearly
three times that of the rest of California. This annual increase has since slowed considerably,
due to both conservation measures and the economic recession. But with improved economic
climate and increasing population growth, the energy use growth rate is again increasing.
Measures both to conserve existing supplies and to develop alternative sources are necessary to
avoid the very real possibility that power demand may exceed supply within the planned future.
San Diego's energy use patterns differ considerably from those of the rest of the nation. Because
local industry in general is less energy-demanding, and because the local climate requires less
heating and cooling, per capita energy consumption is less here than elsewhere in the United
States. However, gasoline accounts for a larger proportion of that per capita consumption. With
low-density development, low mass transit use, and heavy dependence on private transportation,
vast quantities of energy are used to move both people and goods.
Nearly all of the energy consumed in San Diego is in the form of electricity, natural gas, and
gasoline. These end-use energy forms derive from three basic energy sources: oil, hydropower,
and natural gas. One alternative to imported oil is exploitation of local off-shore oil reserves;
conversion to coal, nuclear fission, or geothermal energy to replace oil in the generation of
electricity are other possibilities. Hydropower currently supplies more than a third of the power
used for generating California's electricity, but its possibilities for expansion are limited because
the most economic sites have already been developed. Long-range projects to supplement
natural gas supplies include importation of gas, by either pipeline or in a liquefied state, from
other countries; various innovative processes for synthetic production of natural gas locally; and
substitution of solar energy for some of the natural gas uses, mainly heating and cooling.
Various techniques exist for recovering useful forms of energy from solid waste. These include
burning trash to produce steam, for heating or electricity production; pyrolysis plants to produce
fuel oil from waste; and recovery of methane gas from either sanitary landfills or wastewater
solids. A related reclamation approach is the recycling of specific clean materials, such as
ENERGY CONSERVATION 206
aluminum, copper, steel and paper. Metals can be reclaimed for a small fraction of the energy
required to process raw material. Recycling paper requires a much higher relative amount of
energy, but still can be done cost-effectively and energy-effectively.
Apart from the controversies that surround the development of specific alternative energy
sources, there appears to be general agreement on many aspects of the supply picture. Petroleum
supplies are both limited and unreliable, and must gradually be replaced by other basic energy
sources. There is to date no single non-petroleum energy source which has the promise of
replacing petroleum; therefore, many alternatives must be explored and evaluated. It is
reasonable to anticipate several decades of research, development, demonstration, and
commercialization before many of the non-petroleum energy sources can make a significant
impact on the whole energy problem. The era of cheap and plentiful natural gas for California
appears to be over. New sources for importation may be arranged. But, as other states and other
countries become increasingly concerned about their own energy supplies, these sources can be
considered at best as temporary transition measures.
There is also general agreement that existing ways of life, urban patterns, transportation
facilities, buildings, and equipment all reflect a past when energy was abundant and cheap.
Many other countries, with living standards equal to ours, use less than half the energy per capita
that is consumed in the United States. Apart from savings in transportation, the next most fertile
area for improving efficiency is building and development design and land use patterns. It is
indisputable that sprawled low-density urban development increases travel distances, street and
highway requirements, public utility extensions, and public service costs (fire, police, schools) -
all of which translate directly into increased energy use. Grouped structures and higher density
development have recognized energy savings. Subdivisions in areas that are hot in summer and
cold in winter, or in areas where auto dependence is mandatory, or where cultural and
commercial and recreational and employment facilities are lacking, can only result in increased
energy use - not only in initial development but also in yearly operation and in the more
nebulous energy costs that traffic congestion, wasted water, and public services demand.