Energetica India Magazine May-June 2021

ENERGY EFFICIENCY 43 energetica INDIA- May-June_2021 zero is very hard. But, at this point also imperative. So where do we begin? This is usually the point at which some- one pops up and says, “all we have to do is plant more trees and we will be ok”. The unfortunate reality is that we have passed the point of this being a viable solution. Don’t get me wrong planting trees has many ecosystem benefits, helps in sequestering large amounts of CO2 and should be encouraged. There is just one problem, the numbers do not work out. A fully grown tree (older than 20 years) sequesters approximately 22 Kgs of CO2 a year, so a hundred trees sequester 1.8 tons of CO2/year a million trees 2.2 kilo tons of CO2/year. Sequestering our cur- rent yearly excess emissions will require approximately 28 billion fully grown trees requiring a landmass greater than the size of India and more fresh water and fertilizer than is currently available on planet earth. Other non-trivial challeng- es include the risk of large-scale carbon release on account of forest fires and im - pact on food production. These challenges aside, the main rea- son why planting trees is no longer via- ble is the fact that planting a tree today will meaningfully impact emissions in 20 years, we need to start combating emis- sions right now to stand a chance. So, this takes us back to the question. Where do we start? While there is no easy answer, the most promising answer is Energy Efficiency. There is a triangular equivalence that is now at the heart of the energy transition. “A rupee saved is a rupee earned” is interchangeable with “a watt saved is a watt generated” and also “CO2 avoided is CO2 sequestered”. Money, Carbon and Energy have be- come perfectly convertible. Well, almost perfectly convertible. In practice, saving a watt of power is al- ways cheaper than generating a watt of power, emissions prevented are consid- erably better for our planet than emis- sions sequestered, and this equivalence is often true in the case of money as well, not getting Starbucks is easier than gen- erating a few hundred rupees. However, to illustrate my thesis let’s say that the monetary value attached to savings and generation is the same. Carbon, energy, and money have be- come interchangeable. So, we may as- sume preventing emissions from enter- ing the atmosphere has the same net effect as removing emissions from the atmosphere (in reality, emission prevent- ed to have a considerably more positive impact than emission sequestered) AWatt saved = CO2 avoided = Rupees saved While the Energy Efficiency equivalence is not by any means a silver bullet, it is the lowest hanging fruit in terms of tech- nology, cost, and efficacy. I’d like to illustrate this claim through a brief analysis of greenhouse gas emis- sions by sector. Global energy produc- tion creates 73% of global emissions. This can be divided into emissions from energy use in Industry, which is respon- sible for approximately 24% of global emissions, emissions from energy use in buildings accounting for 17.5% and transport for 16.2% of global emissions. These large sets can be further divided into a large number of emission source subsets, let’s take emissions caused by energy use in building as an exam- ple, this large set makes up 17.5% of global emissions. It can be divided into emissions from energy use in commer- cial buildings making up 6.6% of global emissions and residential buildings ac- counting for 10.9% of emissions. Drilling down further this can be divided into en- ergy use by building type, region, even by individual rooms or perhaps by appli- cation (lighting, cooling, heating etc.). Now imagine energy efficiency mea - sures were implemented at every level. Energy efficiency measures can range from low tech, like a sign reminding peo- ple to switch off lights and fans when not in use to IoT-enabled smart buildings that optimize energy use to high tech solutions like super-efficient appliances like BLDC ceiling fans, inverter ACs and heat pumps. The cumulative impact of aggressive be- havioral changes and technology inter- ventions across emissions sources will by some estimates help reduce global emissions by approximately 30%* by 2040. Energy-related GHG emissions, with and without efficiency, 2000-17 (left) and in the NPS and EWS, 2000-40 (right) *Source: International Energy Agency I believe that one of the biggest threats to our climate future is the fact that we are pinning our hopes on future technol- ogies that may or may not work, there is no guarantee that carbon capture will work or that we figure out fusion energy. Energy Efficiency measures are mostly based on existing mature technologies, represent a minimal financial risk, in fact, Energy Efficiency projects often provide attractive payback cycles. Most importantly EE works. *Source Nature.com