I always look forward to my yearly animated trip up Mount Crumpet. The story centers on a grumpy, sustainability-minded hermit, living off-the-grid and traveling by dog sled. He attempts to curtail the excessive consumption of the townsfolk below. There is some stuff about holiday spirit and heart enlargement, ultimately leading him to join the consumptive revelry. He forsakes his more sustainable lifestyle and is last seen serving environmentally challenged roast beast.
My interpretation of How the Grinch Stole Christmas! clearly evolved. Our behaviors have sustainability implications. Celebrating the holidays is no exception.
I’ve already seen a trove of articles addressing sustainability of the holidays. Chemistry and materials science are foundational technologies in lighting and trees, two areas mentioned frequently in discussions of holiday sustainability.
Consumption is rarely a road to more sustainable. Yet, many propose a way to sustainability is replacement of electric holiday lighting, either with LEDs or with solar powered LED lighting. I am a big fan of LEDs, making my own landscape lighting from discrete LEDs in the days before fixtures were widely available. Landscape lights are on daily for multiple hours per day all year long. I applied life-cycle thinking, making estimates on the energy used to produce incandescent bulbs and LEDs, confirming the net energy savings. I examined the economics, discovering my use pattern consumed sufficient energy for the LEDs to pay for themselves quickly.
Holiday lighting is a very different story. Used for only about a month per year and for limited hours per day, LED economics are unfavorable. I estimate over a 25-year payback based on recent pricing. I’m willing to pay to lower my GHG footprint, but understanding my footprint requires contemplating the full life-cycle, considering the production of the lights as well as their use. GHG emissions come from energy production. Extra energy used in production of the LEDs must be compensated by energy savings during use. Making gross assumptions using published lighting life-cycle assessments gives me confidence use-phase energy savings with LEDs more than compensate for the higher production energy. I estimate the energy break-even at between 3 and 4 years. Use the lights longer than that and I’ve done better for the planet. Throw them away before that and I’d have been better off with incandescents.
Those touting solar lights for the holidays because they won’t use electricity from the grid neglect the energy used during production, and its emissions. A positive energy return is almost impossible for a photovoltaic device used only for a month per year at the worst time of the year for solar energy. A reasonable estimate is over 20 years to breakeven on the energy, much longer than my experience indicates a consumer device coupling a photovoltaic and a battery will last.
Our house is currently illuminated for the holidays with about 300 W of LED and incandescent lighting. No matter how I dice the detailed data provided by my utility, I can’t see a clear rise in consumption on the day we put up the lights or a drop on the day we turn them off. Normal daily variations simply swamp consumption due to holiday lighting. The GHG abatement benefit of full LED conversion is equal to about $900/ton using U.S. grid average emissions factors, estimating a 10 year life for LEDs, and the price of new LEDs, considerably more than the $10-15 cost of an emission offset.
I am not stuck with grid average power. I purchase renewable power. I pay a premium, purchasing all of my average demand and paying less than $1.50 extra per year for all the power used for my current LED and incandescent holiday light mix. By paying more, I’m encouraging renewable power on the grid. It’s a better option than solar lighting fixtures or offsets.
Our tree comes right from the local tree farm. The first reporting I saw comparing the sustainability of real versus artificial trees favored real, concluding it would take 20 years of artificial tree use to be more sustainable, far less than the 6 year average artificial trees are used. That study continues to be quoted. More recent studies show the analysis hinges on disposal of the real tree, potentially reducing the breakeven to as little as 5 years. My particular use case isn’t considered in these studies, leading me to believe my breakeven is longer, closer to 10 years. Real versus artificial seems too close to definitively call.
Now for some Grinchiness. Sustainability and excess are largely incompatible. Preserving resources for the future requires judicious use, not wasteful use. Many holiday activities are unnecessary, optional. We light up, set up and blow up things we go the rest of the year without. We have feasts far exceeding our required caloric intake. During the holiday season, remember the planet and think of future generations. Apply life-cycle thinking as you make decisions about what to do, and what not to do. Make choices that bring you joy, be mindful of the consequences, and choose more sustainable options.
The opinions expressed in this article are the author's own and do not necessarily reflect the view of their employer or the American Chemical Society.