Adan Macias
Martha Townsend
Writing 340
Illumin Article: Self-Sufficient Homes
As time goes by and people become more informed about the harmful impacts we have
on our environment, the more important it has become to take action on the issue in hand. This
new understanding of the negative impacts we promote on the environment has created a demand
for new ways of promoting sustainability, or better yet, sustainable living. As it has been known
for many years, the energy that we use on a daily basis is, by far, one of the most harmful forces
on our environment, because of the use of fossil fuels. Today, as awareness becomes more
evident, architects and engineers have found new ways of helping meet our everyday energy
needs, but more importantly, they have found a way of minimizing our impact on the
environment through a practice that many can follow. This new application is one that is
implemented into projects that are small-scale, best known as self-sufficient homes. Selfsufficient homes provide all of their energy, water and sewer needs, and the designer typically
makes an effort to choose environmental friendly materials. Though, one might argue that the
technology is expensive and the resources are often remote, self-sufficient homes are a great
alternative to reduce the negative impact on the environment.
Self-Sufficient Homes
Self-sufficient homes, also known as net zero buildings, are buildings with zero net
energy consumption and zero carbon emission. In simpler terms, "while it doesn't take your
home off the local utility grid, it will offset the cost of energy a typical family consumes over the
course of a year. Simply put, a net zero home can create as much energy as it uses," says the U.S.
Department of Energy. [3]
Fig. 1. fluxHome active and passive systems diagram.
Diagram provided by Alan Peschard, USC Alumni.
Active Systems
Within self-sufficient homes, there are passive systems and active systems, such as seen
on fig. 1, which can practically run a house without the use of the grid. Active systems are the
systems which implement the sun's energy to produce electrical power. As mentioned, selfsufficient homes produce all their electrical power through the use of solar panels, also known as
photovoltaic panels, and they are less reliant on using the grid, though they are always connected
to the grid. One thing to take note of, however, is the amount of energy that will be produced by
the solar panels. This is based on two main factors, the location of the house and the amount of
energy the user will consume. Once these two things are determined, then one can figure out how
much energy needs to be produced, consequently, identify the number of solar panels needed for
the house. In addition, the solar power can also be used to produce hot water through solar
thermal panels, which essentially work the same way as the solar panels, though one converts the
solar energy into electrical energy and the other uses the solar energy to heat water.
Passive Systems
Passive systems, on the other hand, is a system of natural air ventilation for cooling,
through window and door openings, and capturing the sun's heat, through windows. Opposite
from the active system, the passive system does not require any mechanical equipment or the use
of energy. On the contrary, the passive systems allow for very little or no use of air conditioning
because a house can be cooled off by the natural ventilation, or cross-ventilation, that flows from
an opening on one side of the house to an opening on the opposite side. Similarly, the passive
system helps to heat up a room as the sun's rays enter through a window, which absorbs and
retains heat. Like the active system, the passive system allows for less consumption of electrical
heat. One important factor of passive systems is the orientation and envelope of the house.
Orienting the house to face the direction of the prevailing winds is a crucial factor to allow a
natural breeze to flow through the house. The envelope of the house also plays an important role
because if there are not enough windows or large door openings, then the heating method will
not work effectively.
Water
Finally, there are water collecting systems, through the capturing of rainwater, and the
use of gray water systems. If you collect rainwater that falls from the roof, there can be a
catchment plane and/or gutter that can distribute the water into storage tanks. You can use the
water as it is, without filtering it for watering the garden or lawn. Otherwise, it has to be filtered
to be used for non-potable purposes, such as for showering, washing, and watering plants, but
not for drinking purposes. The gray water system, on the other hand, is recycled water that was
already used in the household and simply gets filtered to be used again for the toilet or for
watering plants, again not for drinking. The advantage of using either of these systems is that it
provides an alternative whenever there is a shortage of water or as a way to substitute the main
water source. In addition, aside from being used in the house, the collected water helps in
avoiding floods or the clogging of city drains.
Why is it important?
The importance of using the methods mentioned above are essential to our daily lives
because of all the benefits it provides to the environment. Some of the fundamental advantages
of using these systems in a small-scale project, like a house, are the environmental benefits and
the fact that these natural sources are infinite. The design of a self-sufficient home, "will make
our families healthier, more secure, and more prosperous by improving our air quality, reducing
our reliance on fossil fuels, curbing global warming, adding good jobs to the economy and when they're properly sited - protecting environmental values such as habitat and water quality",
says the Natural Resources Defense Council. [4] The integration of self-sufficient homes is
important because if everyone implemented the systems, then there would be less need for power
plants that burn fossil fuels, which create pollution and other environmental issues.
Disadvantages
One might wonder why such a beneficial concept has such a low usage rate. One of the
disadvantages of having a self-sufficient home is its cost. For example, the upfront cost of
Photovoltaic Panels is so high that it would take a long time for the panels to pay for themselves.
Another disadvantage of having a self-sufficient home is that the natural sources that are being
used to generate energy are sometimes not available, take the sun for example. According to the
U.S. Energy Information Administration, "the use of renewable sources is also limited by the fact
that they are not always available - cloudy days reduce solar power; calm days reduce wind
power; and droughts reduce the water available for hydropower." [1] However, when the systems
are implemented at a smaller scale, like residential, then all these disadvantages do not always
apply. If at all, the only disadvantage for a self-sufficient home is a cloudy day, but even then, it
would still produce some energy and the rest would be used from the grid. In a location like
Southern California, where we have a lot of sunlight, it is very beneficial, and I would argue that
it is a great investment, given you will be generating energy almost imediately.
Fig. 2. South-East view of the fluxHome.
Photo by Adan Macias
Currently
Currently, self-sufficient homes exist scarcely but it is not something that is difficult to
find in any city or see on the media. For example, recently, the U.S. Department of Energy,
hosted a national competition, in which students design a self-sufficient home. "The U.S.
Department of Energy Solar Decathlon challenges collegiate teams to design, build, and operate
solar-powered houses that are cost-effective, energy-efficient, and attractive. The winner of the
competition is the team that best blends affordability, consumer appeal, and design excellence
with optimal energy production and maximum efficiency." [5] This year, the Solar Decathlon
was hosted in Irvine, California, and USC entered the competition, with the fluxHome (fig. 2),
which I took part in. The fluxHome, is a 900 square foot home, and is designed for Southern
California weather. The house is a net zero plus home, which means that it produces more energy
than it consumes. The design of the house allows for the least amount of energy consumption
and for the most energy-efficiency, through its climate and lighting control systems, which work
as sensors to detect heat, humidity, and amount of light that enter the space. Its large windows
and door openings were built to allow for the most natural ventilation and most natural daylight,
which in part saves air conditioning and lighting energy. The fluxHome was one of 19 houses
that were showcased in the competition, so to say that such designs are not capable of being built
or fully functional would be a lie. The fluxHome is one of many entries that have been very
successful.
Conclusion
Self-sufficient homes are not houses that are new to people. For many years, self-sufficient home
have been a subject discussed in many different fields around the world, namely architecture and
engineering. As we all know, sustainable living has an impact on everyone and everything, both
directly and indirectly. It plays an important role in the production of energy for humans and the
natural environment, but unlike the burning of fossil fuels, natural resources are a much safer
alternative to the production of energy. Today, as the awareness of self-sufficient homes
expands, architects have found new ways of helping meet our everyday energy needs. Not only
can sustainable living be applied in the larger context, through wind turbines or hydropower
(energy produced by flowing water), but it can also be implemented into projects that are smallscale, such as the fluxHome.
Bibliography
[1] "Independent Statistics & Analysis U.S. Energy Information Administration," 1 8 2013.
[Online]. Available:
http://www.eia.gov/energy_in_brief/article/major_energy_sources_and_users.cfm. [Accessed
24 10 2013].
[2] "Penn State College of Agricultural Sciences," 1 1 2013. [Online]. Available:
http://extension.psu.edu/natural-resources/energy/what. [Accessed 15 10 2013].
[3] "Net Zero Homes," 1 1 2013. [Online]. Available: http://www.netzerohomesva.com/.
[Accessed 3 11 2013].
[4] "Natural Resources Defense Council," 1 1 2013. [Online]. Available:
http://www.nrdc.org/energy/renewables/. [Accessed 15 10 2013].
[5] "U.S. Department of Energy Solar Decathlon," 1 11 2013. [Online]. Available:
http://www.solardecathlon.gov/. [Accessed 30 10 2013].
[6] M. Brower, "Renewable Energy," EPA Journal, 1990.