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The Pendulum of Energy Efficiency and the Importance of Human Factors

I have noticed that my lighting industry peers are increasingly focusing on carbon footprint cost and the sustainability of lighting systems.

Commendable use of their time as, from the U.S. Department of Energy to the New York Mayor's Office, the push is for 30 percent energy savings in buildings and the gradual cut of some 40 percent of total carbon emission.

So lighting efficiency is definitely on the radar screen, with lighting retrofits being channeled into compact fluorescent lamps and new lighting systems considering the use of expensive but efficient LED fixtures.

However, increasing imbalance is looming between our eagerness for energy efficiency and our nonchalance for inclusion of human factors and the impact that our energy efficiency measures will have on human health. And this is happening around the world.

A recent report released by the Department for Environment, Food and Rural Affairs in England provides lifecycle assessment of ultra-efficient lamps (pdf) by comparing several indicators such as air impact, water impact, soil impact, and resources impact, but there is no mention of direct human impact.

Similarly, guidelines for LEED certification and green buildings in United States, although well-intentioned, omit data on the impact that energy measures will have on human health. Never mind that scientists and clinicians working around the clock have compiled data on the direct connection between light and human health.

And while research continues, one finding is definitive -- that daylight represents a 100 percent healthy package for people, as it comes with views of nature and modulation of its parameters. We can describe daylight as a symphony of modulating spectrum, light intensities, and distributions with the passage of time. And while this modulation appears to be random, there is an underlying order of constancy in the liveliness and modulation of light.

The daylight cycling is reflected in the way human body functions, with peaks and valleys of hormonal production, with sleep and wake cycles, and with modulation of brain activity. We are basically synchronized with nature.

David Bohm, the quantum physicist, developed the concept of an enfolding and unfolding universe, where the whole is a craftsmanship of interconnected parts, and where the smallest part reflects the whole.

In a similar way the human body reflects the wholeness of nature. It is a simple inference that to emulate the daylight characteristics with electrical lighting systems will be healthy for people, while to use static lighting for people will be unhealthy.

Let's zoom back to the New York Mayor's Long-Term Planning and Sustainability Office leading the implementation of PLANYC 2030, a visionary plan to cut carbon emission and green New York City. A massive re-lamping with compact fluorescent static light is planned, but critical aspects of light and human health still need to be addressed.

For instance, matters that should be considered are the spectral contents of various lamps, the benefits of higher light levels in the morning to boost alertness and human performance, the need for different light levels in the afternoon on short winter days to help offset Seasonal Affective Disorder (SAD), and modulation of light to provide people with sensory stimulation and connectedness with nature.

As in nature, we need lighting systems that have efficient redundancy and provide the spectral and light intensity modulation necessary for every living organism.

The new LED technology is a promising vehicle to achieve lighting that is energy efficient and healthier. Energy efficiency should not only take into account the emission of photons (lumens/watt) but also consider the benefits to human potential and human health.

Why do we have an imbalanced approach to energy efficiency?

Take for example, the recently released Advanced Energy Design Guide for Small Hospitals and Healthcare Facilities. The guide was developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, the American Institute of Architects, Illuminating Engineering Society of North America, U.S. Green Building Council, and the U.S. Department of Energy.

With the best of intentions, these agencies brought together the brightest in the industry to shape this document. Fragmentary specialties were brought together to work as an integrated design team and -- by complementing at best or by compromising at least -- to achieve the benchmark of 30 percent in energy savings.

This was an enormous undertaking that resulted in enormous complexity. Bringing together fragmentary specialties and then trying to coalesce them on the design table is a really difficult process. But most importantly, the central focus was on energy efficiency rather than on the realization that all specialties reflect the same whole -- our human nature. When we center on human factors, integration is natural.

When we are centered on human factors, we think at new levels and have a creative approach for energy saving.

For instance, changing white light to cooler Kelvin lighting shifts the perception or skin sensation to a cooler air temperature, which allows for decreasing the cooling load.

Adjusting light levels in the morning and after lunch allows for the dimming of lights during peak load hours and takes into account the needs of the circadian system.

Use of a few vibrant colors in a space also allows for the dimming of lights while relying on the eye chromaticity channel to preserve the perception of brightness.

Considerations should also include an analysis of glazing tints from a human perspective -- how the tints induce a shift in the daylight spectrum and how that shift affects people.

Optimization of the building envelope and orientation also needs to weigh the impacts on the building's occupants. When we think of a building's skin, we should see an opportunity to connect and work with nature -- rather than a shield against nature. Our whole perspective shifts when we are centered on human factors and healthiness.

Can we have a truly balanced approach to energy efficiency?

Yes, and like Antoine de Saint-Exupéry's "Little Prince," we can observe nature and apply, we can use common sense and apply, and we can use new technology for our humanity.

It's time to include the right brain in our work to solve the energy crisis.

In his book "The Master and His Emissary: The Divided Brain and the Making of the Western World," Iain McGilchrist details how the left and right brain provide different perceptions of the world, and how in the West, the dominant perception is leaning increasingly toward the brain's left hemisphere, rather than swinging like a pendulum between the two halves to create a balance.

McGilchrist describes the left brain as analytical, detail-oriented and holding our survival skills, while the right brain sees context, is relations-oriented and holds the abilities to see "the whole" as well as the interconnectedness of things. The author also warns that the left brain is a specialist in denial and like a sleepwalker will amble oblivious to danger toward the abyss.

With energy efficiency, the hope is that we will wake up before the free fall and as the pendulum swings to the right, we have a moment of opportunity to balance and center our measures on human factors and healthiness.

Milena Simeonova is an architect and lighting designer whose consulting practice specializes in the intersection of design, technology and human factors in lighting.

Lighting images courtesy of Milena Simeonova.


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