Carbon Footprint

Green Productivity: The carbon footprint and LED lighting technology

Estimates suggest that almost half of our carbon footprint is due to electricity and 17% is due to lighting alone.  Electricity can be produced by coal, gas, nuclear plants or by renewable sources like geothermal, hydro, solar and wind power.  Table 1 shows the grams of CO2 equivalent produced when 1 kWh of electricity is produced from different sources.  Most of the electricity is produced by fossil fuel-burning plants, and once the losses in transmission and distribution are accounted for it is estimated that each kWh of electricity consumed equates to releasing 830g of CO2 in the air.

Table 1. Grams of C02 produced when generating 1 kWh of electricity by source.

SourceGrams of CO2 produced
Coal955
Oil893
Natural Gas650
Nuclear Energy60
Hydropower15
Solar Energy40

Save Electricity: Reduce Carbon Emissions

Since almost 830g of carbon equivalents are released in the consumption of 1 kWh of electricity, it follows that carbon emissions can be reduced if electricity consumption is reduced.

Replace traditional lights with LED lighting

LED lamps not only consume a fraction of the energy consumed by traditional lighting, they have the double benefit of lasting up to 30 years and contain no mercury.  Table 2 shows that for a municipality to do nothing except replace 1000 street lights with LEDs, it is possible to reduce their carbon footprint by a whopping 133 tons per year.  To put it into perspective, this savings of 133 tons is equivalent to reducing gasoline consumption by 15,517 gallons per year.  The added benefit is that LED street lights give up to 30 years of hassle-free maintenance.

Table 2.  Reduction in carbon footprint by replacing 1000 streetlight with LEDs

 Traditional LightsLED Lights
# of Lights10001000
Power Consumption (W)/Light250100
KWh (units of electricity used/hour)0.250.1
Hours of Operation/Day1010
Carbon Emissions (tons)/year/lamp0.151480.01818
Reduction in Carbon Footprint (tons/lamp)0.1333
Carbon Emissions (tons)/year/1000 Lights151.4818.18
Reduction in Carbon Footprint (tons)/1000 Lights133.3

Why carbon footprints?

Thinking about carbon footprints is a simple way of thinking about ways to reduce environmental pollution, wish is one of the main pillars of Green Productivity (GP). By reducing our carbon footprints, each one of us can contribute to making the earth a safer, better place to live.