Earth Hour – Is it worth the effort?

Guest post by Russ Rodrigues

On Saturday, March 31st at 8.30pm (local time) WWF is inviting you and everyone around the world to celebrate Earth Hour 2012 by turning off non-essential lights for sixty minutes to “protect the planet”.

Now, I’m all for saving electricity and lowering my utility bills, though I can’t help but wonder… does the collective action of millions of people turning off their lights have any real, tangible impact on our planet?  Can an hour of conspicuous conservation actually help us achieve our greenhouse gas (GHG) emissions reduction targets?  Or is Earth Hour merely another exercise in self-satisfying slacktivism, achieving nothing more than the squishy “feel-good” objective of “raising awareness”?

To answer these questions and get a sense of how effective Earth Hour really is, let’s look at the results of last year’s effort, specifically in the province of Ontario, Canada (where I happen to live).

Ontario’s Independent Electricity System Operator (IESO) reported that that on March 26th, 2011, between 8:30pm and 9:30pm, due to conservation action during the last episode of Earth Hour, province-wide demand for electricity fell by 360 megawatts or 2.1% compared to a typical Saturday evening in late March.

Let’s simply assume that all 360 MWh of power demand was actually eliminated, rather than being merely postponed.  Since it would be difficult to quantify the impact of time-shifting household activities, let’s just be generous and ignore it altogether.

How big a deal is 360 MWh?  At Ontario’s blended average retail electricity price of 7.74 cents per kWh, that 360 MWh of reduced consumption amounts to a province-wide total cash savings of $24,864.   One could, perhaps, compare that savings to the money spent promoting Earth Hour in Ontario by the WWF, various levels of governments, and numerous corporate partners, to say nothing of the costs incurred by the individual participants.  But I don’t imagine that would be a favourable comparison.

So cost savings aside, how big an impact did Ontario’s Earth Hour have on the province’s CO2 emissions?  Let’s ignore the extra emissions generated by people who traveled to and from public gatherings, or by those who lit paraffin wax candles (each of which emits about as much fossil-fuel derived CO2 per hour as a compact fluorescent light bulb). For simplicity, we’ll just focus on the CO2 emissions from the electricity that was saved.

According to the Environmental Protection Agency (EPA), non-baseload electricity emits an average of 690 g of CO2 per kWh into the atmosphere.  So, by simple math, by conserving 360 MW of electric power during Earth Hour, Ontarians reduced their CO2 emissions by a total of 248 metric tonnes.

248 tonnes.  That sounds pretty impressive, doesn’t it?  And it isn’t really that difficult to achieve… in fact, it’s even kind of fun.  Perhaps we could just have a few more Earth Hours each year, and have some real impact on our emissions reduction targets.  So, how many Earth Hours would it take?  Once every quarter?  One per month?  Or maybe make it a fortnightly event?

In 2007, Ontario introduced its Climate Change Action Plan action to reduce total GHG emissions. This action plan established an annual GHG reduction target “6% below 1990 levels by 2014, a reduction of 61 megatonnes relative to business-as-usual” (pg 6).  By eliminating 248 tonnes of CO2 emissions, Earth Hour achieved 0.000407% of this target.

Or, looked at another way, it would take nearly 246,000 Earth Hours to achieve the province’s annual emissions reduction target.  Unfortunately, there are only 8760 hours in a year, so it would require a little more than 28 years of sitting in the dark to make good on a single year’s emissions reduction target.  The WWF certainly isn’t kidding when it asks Earth Hour participants to sustain their actions “beyond the hour.”

But details like this aren’t what Earth Hour is about.  It’s about demonstrating our commitment to the planet… about taking a stand on climate change… about promoting environmental consciousness.  It’s a symbol of hope for the future.  It’s an opportunity to light lots of pretty candles (preferably of the carbon-neutral, beeswax variety) and unite as a community in celebration of… well, uniting as a community.  Yes, it’s all that and countless other fluffy intangibles.

So, you might as well just enjoy Earth Hour.  While switching off your lights won’t achieve any material impact in terms of reducing emissions or protecting the planet, at least you can shave a bit off your electric bill while feeling good about yourselves.  And of course, you’ll be doing your part to “raise awareness”.

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Spreadsheet for the calculations: Earth Hour Calculations (.xlsx)