July 31, 2021
By Bani Pouyanfar
US energy use is about the same now as it was in 2000, despite economic growth of about 30 percent. Wondering why?
The short answer is energy efficiency. In fact, energy efficiency has done more to meet America’s energy needs than oil, gas, and nuclear power over the past four decades and already accounts for over 2.2 million U.S. jobs—10 times more than oil and gas drilling and 30 times more than coal mining.
What is Energy Efficiency?
In general, energy efficiency refers to using less energy to produce the same amount of work, service, or useful output. It is considered the key means for reducing greenhouse gas emissions and achieving other energy policy goals. Several indicators are defined to quantify and monitor changes in energy efficiency, but at the end, it is a simple ratio of useful energy output over energy input. Energy efficiency matters simply because our main energy resources are limited.
We hear the example of light bulbs all the time: how swapping an old incandescent one with a LED bulb would use less energy for the same amount of light. However, the concept is far more extensive—energy efficiency is an important tool that helps reduce pollution and waste.
Energy efficiency is a hot topic these days and it is being discussed in detail in every single aspect of life – and not only human life. Here we explore energy efficiency in categories which are related to our modern lives and could be informative and helpful for people living in urban areas; buildings, transportation, and the food industry.
Energy Efficiency in Buildings
The buildings sector, including residential and industrial buildings, accounts for about 76% of electricity use and 40% of all US primary energy use and associated greenhouse gas emissions. This alone is enough for us to admit that energy efficiency has a huge impact on overall electricity and energy consumption nationwide.
In order to have a more efficient living space, urban communities could focus on three main categories: air conditioning, lighting, and appliances. Energy Star appliances can save 10 to 50 percent of the energy required.
Now let’s talk about air conditioning and lighting. About 85% of the energy consumed in buildings is used for heating, lighting, and hot water. A lot of this energy could be saved by increasing the insulation of the building, or by using efficient heating, cooling systems and/or using sunlight as lighting during the day. That is where the concept of Passive House was introduced; a Passive House is a building that has a comfortable indoor temperature during winter or summer, with a low energy request for heating or cooling of the space. Essentially, it requires less energy and its designs are achieved by using low conductivity windows and effective shading designs.
Energy Efficiency in Transportation
Today, transportation is the leading source of greenhouse gas emissions in the U.S.. Divided by source, light duty vehicles account for about 60% of that amount. This is basically what we contribute to every day by driving our cars. We cannot tackle climate change goals without improving the transportation sector.
Energy efficiency can be viewed from two different perspectives: efficient transportation systems and efficient vehicles (which include fossil-fuel and electric vehicles). On a realistic note, we cannot wipe out every vehicle and replace them with electric vehicles, but it is all about small changes made by a lot of people. The impressive thing about electric vehicles is that they are three to four times more efficient than gasoline vehicles. Also, the electricity required for electric vehicles is all produced domestically, which reduces the need to import oil and helps with saving energy on transporting fuel.
In addition, an efficient transportation system matters, because it considers different aspects like traffic management, environmental considerations, mobility, and public health all together. It also helps encourage new policies, incentives and related programs.
So yes, switching to green vehicles is definitely something to think about; but maybe more importantly, we should choose policy makers who share our concerns and can act accordingly. Have you seen our latest blog on NYC mayoral race?
Energy Efficiency in Food Industry
It is estimated that the food system contributes to nearly 15% of total US energy demand. From farm to plate, our food has four main parts: agriculture, transportation, processing, and handling. Despite all the improvements in related technologies, these steps are highly inefficient.
The energy used to make food is vastly greater than the amount of energy we get out of it; for example, the ratio is about 10 to 1 in the US (meaning it takes about ten units of energy per each human). This takes into account all the energy that goes into our freshwater supply, fertilizer, transportation, processing, storing, refrigeration, and handling in general. However, the scariest part is that about 30 to 40 percent of our food supply is food waste! Can you just imagine how much energy (and money) we lose to have one decent plate of food?
Given the predicted population growth, this does not get any better unless we reconsider our food basket. The FAO (Food and Agriculture Organization of the UN) recommends that we buy only what we need, pick ugly fruits and vegetables (to keep them from being thrown away), shop local, eat more grains and veggies, and compost, which gives nutrients back to the soil.
Energy efficiency matters! It is not just about the sources of energy; it is about the limited supply of earth’s natural and mineral resources. We are responsible for our lifestyles, for what we eat, where we live, what we drive, and what we leave for the people to come.
Interested in learning more about energy around the world? Check out our upcoming August Monthly Forum event to learn more.