502
In contrast to centralized systems, decentralized systems have the potential to
provide diverse, resilient, and sustainable FEW supplies. Examples of decentralized
FEW supplies include urban gardens, urban agriculture, green stormwater infrastructure (e.g., green roofs, rain gardens, cisterns, rain barrels), and decentralized
energy systems (e.g., individual rooftop solar supply, mini- or community grid, and
distributed individual energy services). The short supply chains (SSC) characteristic of decentralized systems can be more environmentally friendly by reducing the
number of intermediaries and the transportation distance between FEW commodities and consumers (lighter footprint). For example, supply chain analysis and/or
life cycle assessment of decentralized systems may compare the energy efficiency
of local food systems to long supply chains and demonstrate that urban agriculture
has the better energy performance and can also reduce greenhouse gas emissions.
There is much debate about the overall relative sustainability and efficiency of
centralized versus decentralized systems. Although decentralized systems reduce
transportation distance and intermediaries, the consequent decrease in initial energy
consumption may be offset by other energy uses (such as for food storage). Similarly,
socio-economic benefits related to decentralized FEW system employment (more
local jobs demanding skilled workers that receive higher wages) that may be lacking
in centralized systems—due to resource extraction and production distant from the
city—may result in drawbacks relating to commodity pricing and stability.
Conversely, although decentralized FEW supply chain performance may be undermined by a weak structural optimization of supply logistics, centralized supply
sometimes results in severely under-served populations (represented by the lack of
affordable fresh food in urban centers, the lack of dependable water in low income
areas of cities in developing countries, and the lack of energy following disasters
caused by weather).
Certainly, the development of decentralized FEW supplies in cities faces numerous obstacles due to the scarcity, expense or fragmentation of land, and the challenge of integrating innovative practices with existing infrastructure (see the
examples in Sect. 18.5 below). The sometimes controversial social, economic, and
environmental impacts of urban FEW innovations include odor (from waste stream
recapture and larger farm animals), noise (from wind generators and chickens), and
perceived aesthetics and safety (from tall vegetation in gardens and stormwater
management systems). Future research on both centralized and decentralized systems is warranted using more holistic assessments and considering design logistics
within a framework of sustainability’s triple bottom line, which considers social,
economic, and environmental impacts, as discussed further in Chap. 22.
18.3.3.2 Integrated Versus Separated Systems
The complexity and historical structure of energy, water, and food systems typically
result in separate management of their various elements, despite their numerous
interwoven interactions. Examples of separate systems include groundwater pumping to supply a city, conventional tillage of an agricultural commodity by a farm for
C. Harris et al.
In contrast to centralized systems, decentralized systems have the potential to
provide diverse, resilient, and sustainable FEW supplies. Examples of decentralized
FEW supplies include urban gardens, urban agriculture, green stormwater infrastructure (e.g., green roofs, rain gardens, cisterns, rain barrels), and decentralized
energy systems (e.g., individual rooftop solar supply, mini- or community grid, and
distributed individual energy services). The short supply chains (SSC) characteristic of decentralized systems can be more environmentally friendly by reducing the
number of intermediaries and the transportation distance between FEW commodities and consumers (lighter footprint). For example, supply chain analysis and/or
life cycle assessment of decentralized systems may compare the energy efficiency
of local food systems to long supply chains and demonstrate that urban agriculture
has the better energy performance and can also reduce greenhouse gas emissions.
There is much debate about the overall relative sustainability and efficiency of
centralized versus decentralized systems. Although decentralized systems reduce
transportation distance and intermediaries, the consequent decrease in initial energy
consumption may be offset by other energy uses (such as for food storage). Similarly,
socio-economic benefits related to decentralized FEW system employment (more
local jobs demanding skilled workers that receive higher wages) that may be lacking
in centralized systems—due to resource extraction and production distant from the
city—may result in drawbacks relating to commodity pricing and stability.
Conversely, although decentralized FEW supply chain performance may be undermined by a weak structural optimization of supply logistics, centralized supply
sometimes results in severely under-served populations (represented by the lack of
affordable fresh food in urban centers, the lack of dependable water in low income
areas of cities in developing countries, and the lack of energy following disasters
caused by weather).
Certainly, the development of decentralized FEW supplies in cities faces numerous obstacles due to the scarcity, expense or fragmentation of land, and the challenge of integrating innovative practices with existing infrastructure (see the
examples in Sect. 18.5 below). The sometimes controversial social, economic, and
environmental impacts of urban FEW innovations include odor (from waste stream
recapture and larger farm animals), noise (from wind generators and chickens), and
perceived aesthetics and safety (from tall vegetation in gardens and stormwater
management systems). Future research on both centralized and decentralized systems is warranted using more holistic assessments and considering design logistics
within a framework of sustainability’s triple bottom line, which considers social,
economic, and environmental impacts, as discussed further in Chap. 22.
18.3.3.2 Integrated Versus Separated Systems
The complexity and historical structure of energy, water, and food systems typically
result in separate management of their various elements, despite their numerous
interwoven interactions. Examples of separate systems include groundwater pumping to supply a city, conventional tillage of an agricultural commodity by a farm for
C. Harris et al.