EFFICIENT ENERGY PLANNING
Resiliency and sustainability of design
will be gained by use of renewable energy sources. Techniques
that harness sun, wind, water and biomass are diverse and small-scale
but can be designed to effectively serve the needs of many sites.
Efficient energy planning is intended to maximize the use of wild
and site-related energies and minimize human and external energy
inputs. Energy flow on a site is enhanced by intercepting and
recycling the flow across the site. Solar energy is stored in
plants and physical mass; water is held by ponds, plants and mulch;
wind can be concentrated with building or plant placement. Energy
is cycled as kitchen waste is converted to compost, animal manures
to biogas production or soil enhancement, greywater to garden
irrigation, green cover crops to green manure, and organic matter
to mulch. The goal is to catch, store, use and recycle every energy
source as it degrades across the site and is finally lost to us
forever.
The sources of wild energy may be determined as a starting point
for a design. In doing an analysis of a site the directions from
which the wild energies originate can be plotted. Certain slopes
are receivers of the most intense solar radiation; winter or tropical
storms may originate from predictable directions; prevailing wind
directions are known. Simple formulas can be used to determine
water volume and runoff under different storm conditions. Permaculture
approaches such as zone and sector planning assist in the design
of efficient energy systems.
Efficient energy planning is related to use of energy flow. Energy
is either in storage or somewhere driving a landscape process.
Lyle, in Regenerative Design
for Sustainable Development , identifies six basic phases
of ecosystem functioning (pg. 26-27). Driven by solar energy,
these six connected processes are conversion, distribution, filtration,
assimilation, storage and human thought. By understanding these
processes we can optimize energy flows.
Energy flow is made usable by intercepting and recycling the
flow of energy across the site. While no energy is lost in passage
through the site, it is degraded from a concentrated to a more
dispersed form. However, techniques can be used to concentrate
energy in the short term for more efficient use on the site. There
are numerous approaches to making efficient use of solar, wind
and water energy.
- Solar energy is used by plants that convert light to biomass
to be used eventually as compost, mulch or fuel. Water plants
may be used to extract nutrients from the water. These plants
may, in turn, be used as animal food or composted.
- Wind energy can be concentrated with tree or hedge plantings
or building placement to increase the speed of the wind as it
is forced into a constricted area. Towers can be used to draw
wind into a structure for ventilation.
- Water running onto, through, then off of our site can be
used to advantage. Elevation and water management planning is
a well known permaculture technique. Water is stored in ponds
or cisterns and its flow across the site is controlled for irrigation
or power needs.
