493
and pelletized biosolids as fertilizer to urban and peri-urban farms and home
gardeners, although the possible presence of pathogens and low-level persistent pollutants such as PCBs, dioxin or heavy metals may limit land-application of treated
sewage sludge in some areas and depend on its treatment.
While innovative individually implemented solutions may not be public in scope,
they often require substantial public discourse and policy revisions to be able to
implement. Putting treated household wastewater directly back into the household
water supply system (through greywater systems or pee-cycling) reduces the energy
required both for water supply and treatment, and dry toilets (either urine-diverting
or composting) can somewhat reduce pressure on water supply while reducing the
need for wastewater treatment and supporting the reuse of human excreta for agriculture. These household- and facility-scale solutions demonstrate that although the
density of human population and industry in cities concentrates related water quality
impacts there, supportive public policy and education to promote these solutions
have the potential to support greater food, energy, and water security.
18.2.2.3 Energy Systems
Municipal governments that are energy providers may be able to improve upon the
public benefits that private energy providers supply in that they can coordinate the
provision of energy with land use planning and other municipal services (e.g., water
and wastewater, transportation). One example of this is the creation of heating districts where the generation of electricity is used to produce hot water (as in Detroit,
see Sect. 18.5.2) for residential and commercial heating or for industrial uses or for
hydroponic and aquaponic agriculture.
Other cities are piloting electricity generation from the water flowing through
their water infrastructures (as in Portland, see Sect. 18.5.1). Some cities have begun
installing wind generation and solar collection capacity on public land to feed into
the local electric grid, and some coastal cities are exploring the possibilities of
tidal power.
In addition, some cities have adopted policies mandating that all energy used
by the city and its agencies come from renewable sources (i.e., hydroelectric,
wind, solar). In some cases, public hydroelectric dams have had the unanticipated impact of creating fishing opportunities that provided food for segments of
the local population, and in other instances, public investments to mitigate fisheries damage due to private dams have been necessary (criticality and affordability
criteria).
One of the important dimensions of smart cities is the reduction of energy use
for transportation (to see how one Brazilian city has achieved this, refer to Sect.
18.5.3 on Curitiba). City policies increasing densification in order to reduce energy
consumption can help urban areas transition toward sustainability, with intentional
ecovillages designed for efficiency of the production and consumption of energy,
water, and food (as in Tianjin, refer to Sect. 18.5.4).
18 Cities at the Nexus
and pelletized biosolids as fertilizer to urban and peri-urban farms and home
gardeners, although the possible presence of pathogens and low-level persistent pollutants such as PCBs, dioxin or heavy metals may limit land-application of treated
sewage sludge in some areas and depend on its treatment.
While innovative individually implemented solutions may not be public in scope,
they often require substantial public discourse and policy revisions to be able to
implement. Putting treated household wastewater directly back into the household
water supply system (through greywater systems or pee-cycling) reduces the energy
required both for water supply and treatment, and dry toilets (either urine-diverting
or composting) can somewhat reduce pressure on water supply while reducing the
need for wastewater treatment and supporting the reuse of human excreta for agriculture. These household- and facility-scale solutions demonstrate that although the
density of human population and industry in cities concentrates related water quality
impacts there, supportive public policy and education to promote these solutions
have the potential to support greater food, energy, and water security.
18.2.2.3 Energy Systems
Municipal governments that are energy providers may be able to improve upon the
public benefits that private energy providers supply in that they can coordinate the
provision of energy with land use planning and other municipal services (e.g., water
and wastewater, transportation). One example of this is the creation of heating districts where the generation of electricity is used to produce hot water (as in Detroit,
see Sect. 18.5.2) for residential and commercial heating or for industrial uses or for
hydroponic and aquaponic agriculture.
Other cities are piloting electricity generation from the water flowing through
their water infrastructures (as in Portland, see Sect. 18.5.1). Some cities have begun
installing wind generation and solar collection capacity on public land to feed into
the local electric grid, and some coastal cities are exploring the possibilities of
tidal power.
In addition, some cities have adopted policies mandating that all energy used
by the city and its agencies come from renewable sources (i.e., hydroelectric,
wind, solar). In some cases, public hydroelectric dams have had the unanticipated impact of creating fishing opportunities that provided food for segments of
the local population, and in other instances, public investments to mitigate fisheries damage due to private dams have been necessary (criticality and affordability
criteria).
One of the important dimensions of smart cities is the reduction of energy use
for transportation (to see how one Brazilian city has achieved this, refer to Sect.
18.5.3 on Curitiba). City policies increasing densification in order to reduce energy
consumption can help urban areas transition toward sustainability, with intentional
ecovillages designed for efficiency of the production and consumption of energy,
water, and food (as in Tianjin, refer to Sect. 18.5.4).
18 Cities at the Nexus