Now that Earth Day 2009 Is Over, NOW WHAT?

I don’t know if you are like me, but when I opened my inbox today it was filled with ump-teen emails regarding Earth Day.  Save the planet was the model for all and how their product or service would help save the environment.  I related the experience to the overwhelming throng of people who end up in Church on Easter Sunday or Christmas Eve only to find the next week a half vacant church. On this Earth Day, I chose to wait till the day after to post to my blog as it isn’t the” one day a year that someone makes a difference to our environment, it is the forward moving commitment everyday that gets the job done. If we were to change our focus to “Earth Month” or Earth Year” not only would we produce a true impact to the ills in our environment, but we would open our eyes and see that going green actually makes you green dollars in the process. 

Yesterday, in the Earth Day edition of USA Today, the paper focused on Walmart and their expanded commitment to utilize solar photovoltaics in their stores sustainable initiatives. The Skylights in the article photo are high performance prismatic skylights and to date, Walmart has utilized high performance prismatic skylights in over 2,300 of their properties world wide for their daylight harvesting initiatives. For comparison sake, when Walmart installs Sunoptics on of their 200,000 square foot facilities that has a 1.2 watts per square foot lighting load, Walmart has published that on average they are able to shut their lights off in the store for 2,800 hours a year (more to the southern hemisphere). The green energy opportunity for that sample store is the following:

1.2 watts per square foot x 200,000 sq. feet = 240,000 watts or 240 KW of lighting load. 240 KW lighting load x 2,800 hours a year of lights off in the store (Walmart published data) = 672,000 KW per year in electric energy savings just from lighting (does not include the reduction to A/C that each store sees through daylighting. This is a 254% better green energy solution for Walmart per store then the solar panels can produce. Knowing that the cost per KW of PV is still in the several thousand dollar range, our product is a mere fraction of the cost for photovoltaic cells for more than double the performance. After all, in many industrial, commercial and retail facilities, the highest energy usage comes from the building’s lighting system as well as the A/C needed to cool lighting. ASHRAE recognizes this, California Title 24 recognizes this and both code bodies have changed their standards to increase daylighting with lighting controls in their standards.

This comparison is published not to put down photovoltaic. With all the emphasis on the technology, eventually PV will become more efficient and through economies of scale, more cost effective. However, If you figure that to date high performance prismatic skylights have been installed in more than 2,300 Walmart properties around the world over the last 15 years, this would equate to an annual average savings greater than 1,478,400,000 KW per year for Walmart. Annually, with this data, Walmart prevents the emission of 781,042 tons of Carbon Dioxide (CO2), in addition to generating economic savings for the company.

If you take into consideration that the U.S. Average combined demand and supply cost per kWh for electricity is currently $0.12, then Walmart saves approximately $177,408,000 in electricity just from light energy savings through Sunoptics (this does not include the savings they save from electricity due to A/C reduction as well). Walmart published an annual savings per store of $100,000 in the recently released book, "ICSC Retail Green," by Jeffrey M. Bedel. This is a larger dollar value of savings then stated above, but we like to be conservative.

We write this posting for comparison sake and to show you the opportunity of our passive solar technology. High performance prismatic daylighting is the most cost effective and energy efficient solar option for the majority of industrial / commercial buildings. I salute the daylighting and sustainable efforts that Walmart has completed for more than 15 years and the fact that the simple technology of daylighting is playing a major part in reducing the carbon footprint of one of the largest corporations in the world. After all, as I always say, THERE’S NO GREATER EFFICIENCY THAN OFF!