ASHRAE Journal - October 2019 - 61

COLUMN ENGINEER'S NOTEBOOK

Systemic Conservation
Viewed in the context of actual human needs, conservation takes on a new meaning encompassing the traditional idea of efﬁciency improvement and reduction of
losses, but also the new idea of "systemic conservation"-
changing the means of meeting human needs to reduce
or eliminate end-use energy consumption. Systemic
conservation should not be confused with "curtailment,"
which implies a reduction in quality of life in pursuit of
reduced energy consumption. Below are some common
examples of curtailment compared with traditional efﬁciency improvement.
* Drive less vs. drive a hybrid electric vehicle;
* Turn down the thermostat and wear a sweater in the
winter vs. re-insulate the house;
* Reduce ventilation rates, impacting air quality vs.
use heat recovery ventilators;
* Work in the dark vs. use LED lamps; and
* Watch less TV vs. get an LED ﬂat screen.
Systemic conservation, on the other hand, involves
more fundamental changes in the way we meet human
needs-not to diminish quality of life, but rather to
reduce the inherent energy intensity of how we provide
that quality of life. Systemic conservation means reenvisioning the process by which human needs are met,
either eliminating the end-use energy requirement to
meet a human need or changing the process to minimize
the need to provide that end use. Even so, proposals for
"systemic conservation" should be evaluated using the
same process, described below, that would be applied to
simple technological innovations or substitutions. Some
examples of "systemic conservation" include:
* Reducing vehicular trafﬁc by using zoning regulations to encourage development around transit centers;
* Locating data centers in cold climates to enhance
"free-cooling";
* Use telepresence for business interactions instead of
personal travel; and
* Use micro-cogeneration to meet local requirements
for low-grade heat (such as domestic hot water).
The ﬁrst step to controlling our energy appetite is to
review the basic processes by which we meet our societal
needs and evaluate any proposed modiﬁcations to these
processes using the procedure described below.

The Four Components of Conservation Analysis
Four basic characteristics of our energy supply system

should be considered in the evaluation of proposed
technical solutions or improvements:
* Sourcing overhead;
* Conversion efﬁciency;
* Transport efﬁciency; and
* Storage efﬁciency.
The discussion of sourcing overhead will also include a
discussion of what exactly is an energy source, because
many forms of energy that are called sources aren't
really source, rather they are converted forms of some
other source.

Sourcing Overhead
An energy source can be deﬁned as a form of energy
entering the biosphere. Following are the most commonly identiﬁed sources:
* Fossil fuels extracted from the lithosphere;
* Nuclear fuels also extracted from the lithosphere;
* Geothermal (high-grade heat) extracted from the
lithosphere;
* Solar energy (includes direct solar radiation, wind,
wave, biofuel and hydroelectric); and
* Astronomical (tidal).
Note two of the forms of energy, hydrogen and electricity, are not listed here as sources because they are conversion products of other energy sources. Some energy
sources must be extracted from their normal repository by means that can be environmentally disruptive,
including strip mining of coal, and, possibly hydraulic
fracking to free natural gas from shale, while others
require signiﬁcant processing before they are useful as
an energy source. Sourcing overhead, therefore, should
include the energy cost, operational cost and environmental impacts, not only of extraction, but also of converting any raw source to a usable form.
Once the original source of an energy product is traced
back to its source, the sourcing overhead can be evaluated. Criteria for this evaluation include:
* Environmental damage: emissions to air and water,
thermal emissions, waste discharge;
* Resource intensity: water usage, land usage, raw
materials requirements, etc.;
* End of useful life impacts: nuclear waste storage,
recyclability of equipment, disposal; and
* Sustainability: unlimited long-term supply and
social equity of the resource.
For example, one of the current requirements for
O C T O B E R 2 0 19

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