Key Observations:

• About 84% of our energy needs come from fossil fuels that emit greenhouse gasses
• About 16% of our energy needs come from renewable, non-greenhouse gas emitting energy. Half of that comes from Nuclear energy. Practically all of these renewable energy sources goes to the making of electricity
• About 38% of our energy needs go to generating electricity
• About 61% of our energy needs go to non-electric consumption, such as the Transportation, Industrial, and Commercial sectors
• Two-thirds of all energy used is wasted (aka: Energy Rejected), in the form of heat and other by-products
• There are many ways we can reduce our energy consumption and carbon emissions

Understanding Energy

One of the most useful ways to really understand how we use energy and to know where that energy comes from is by using this flow chart (known as a Sankey Diagram) produced annually by the Lawrence Livermore National Laboratory. In this article, I will explain the chart and point out some very interesting facts. I will also suggest some questions to consider, so that we may look deeply at what's at stake for our future and the future of our children.

In the US, we use roughly 100 quadrillion Btu’s of energy per year (which is about 18% of the global energy used. China uses about 70% more energy than the US. The United Kingdom uses about 93% less than the US).

Briefly, a Btu (British Thermal Unit) is the amount of energy needed to heat one pound of water by one degree Fahrenheit. One Btu is equivalent to the amount of energy produced from the burning of one large kitchen matchstick.

• One kilowatt hour (kWh) of electricity, which is the amount of energy it takes to light an efficient LED lightbulb for a week, equals 3,600 Btu’s.

• One gallon of gasoline equals 120,000 Btu’s.

As you look at the chart above, it “reads” left to right. (If you are an audio/visual learner, here is a video that explains how to read the chart.) On the left, you have all the energy resources from which our energy needs come.

Since we have a base of about 100 “quads,” we can conveniently refer to percentages instead of Btu’s. As you can see on the lower left, the US uses about 37 quadrillion Btu’s of Petroleum, out of the total of about 100 quadrillion. So, about 37% of our total energy needs come from Petroleum. By contrast, Solar Energy represents just under 2% of our total energy needs.

On the left, the brownish box at the top middle represents the amount of Btu’s needed for Electricity Generation. The greatest portion of our total energy needs (38%) is used for generating electricity. Notice that most, if not all, of the “Renewable Energy” sources, such as Solar, Hydro, Wind, Geothermal, and Nuclear, are dedicated to Electricity Generation. These sources represent 43% of the energy used to generate electricity.

Meanwhile, fossil fuel sources like Natural Gas (the blue line, 12.5 quads) and Coal (the black line, 8.9 quads) represent 57% of the energy needed for electricity generation.

On the right side of the chart, the four pink boxes represent the sectors where this energy flows and is consumed: Residential (households), Commercial (offices, hospitals, schools, restaurants), Industrial (factories, mining, agriculture), and Transportation (planes, trains, automobiles, and large container ships). Within these four sectors, the Transportation sector consumes the most energy, about 28%.

All the way to the right are two additional boxes labeled Energy Rejected and Energy Services. Energy Rejected refers to the energy lost, such as the heat energy expelled from your car’s exhaust system. Energy Services refer to the energy that powers devices like your car or dishwasher to perform work.

Aha Observations

Every time I look at this chart, I discover something new. Although it may be confusing at first, several observations can be made:

• About 84% of our energy needs come from burning fuels that emit greenhouse gases: Petroleum (37%), Biomass (5%), Coal (11%), and Natural Gas (32%). Although biomass is not a fossil fuel, it is derived from renewable plants like corn and is still burned.
• The remaining 16% of our energy needs come from renewable, non-greenhouse gas-emitting sources, all of which are used for electricity generation. However, over half of this comes from Nuclear Energy, meaning only around 8% of our total energy needs are met by "clean" renewable sources such as solar and wind.
• About 61% of our energy needs are non-electric, mainly consumed by the Transportation sector (powered by gasoline, diesel, and jet fuel), the Industrial sector (which often requires high heat and specific chemical reactions), and the Commercial and Residential sectors.
• Only a third (33%) of the energy we use is actually converted into work as Energy Services. The remaining two-thirds is wasted, or Energy Rejected, in the form of heat and other by-products.

So Now What?

Here are a few questions raised by this data:

Transition to Renewable Energy: How are we going to increase the current 8% of clean renewable energy sources like solar and wind to 100% (or even 50%) of our energy needs by 2030, or even 2050, without drastically reducing energy consumption and dramatically increasing investment in renewable energy?

• We also need to consider the amount of fossil fuel energy required to extract and produce the materials for renewable energy sources. Can this be done without impacting the environment and local communities, particularly in poorer nations where many of these materials are mined?

Electrifying Non-Electric Sectors: Since about 61% of our energy sources are from fossil fuels serving non-electric energy needs, how do we convert those sectors to primarily use electricity? This includes sectors like Transportation (to power vehicles), Industry (to produce materials like steel and concrete), and Residential and Commercial (to cook food and heat spaces). Additionally, many products such as plastics, chemicals, and fertilizers are derived from petroleum. Can these processes ever be electrified?

Improving Energy Efficiency: One of the most startling aspects of our energy consumption is the inefficiency inherent in the system. Nearly two-thirds of all energy used is wasted, primarily as heat and other by-products. This "rejected energy" represents a significant amount of potential power that is lost and not utilized effectively. Improving energy efficiency and reducing waste could have substantial benefits for both the economy and the environment.

• It is imperative to demand the design and engineering of ultra-efficient machines. Since much of the waste comes from the extraction and transportation of fossil fuels, we must further reduce our reliance on them.
• Renewables like solar and wind can be generated with minimal energy losses, as they don’t require heat generation or extensive processing like fossil fuels do.
• Locally generated renewable energy, such as rooftop solar, reduces the need for transportation and transmission, further minimizing energy loss.

Addressing Greenhouse Gas Emissions: Burning fossil fuels and biofuels creates greenhouse gases that contribute to global warming and harmful climate changes. In the U.S., roughly 5 to 6 billion metric tons of CO2 equivalent are emitted annually.

For perspective, a small car weighs about one metric ton, so a billion metric tons of CO2 is equivalent to the weight of a billion small cars!

The chart on the right indicates that drastic changes are necessary to reduce and eventually stop the continuous emission of greenhouse gases.

• This does not even address the CO2 already in the atmosphere that needs to be captured or sequestered. Even if we stopped burning all fossil fuels today, the atmosphere would still contain a significant amount of carbon gases that persist for a long time. We must consider whether there are effective technologies to trap and store these gases, beyond natural processes like carbon sequestration by trees and oceans, without relying on burning fossil fuels.

It seems that we have dug ourselves into a deep hole. My intent here is not to induce apathy, but to provide a clearer picture of our current predicament. By understanding these facts, we can face our reality and take the necessary actions—now—to help save the planet.

What Are Some Things We Can Do?

We can reduce our carbon emissions by lessening our energy usage. About 40% of carbon emissions come from households simply doing what we do every day: driving, heating and cooling our homes, eating, and managing our waste. Using the tools on the website Napa County Climate Challenge.org, we can first calculate our emissions and then take effective actions to reduce them. Not only can we save money, but we can also collaborate with fellow concerned Napans. By working on the site, I was able to reduce my emissions by 76%. It's a start. Join our Napa Sierra Club Team today.

• Theoretically, by reducing our own emissions, we reduce the demand for them, thereby forcing the fossil fuel industry to reduce the production of fossil fuels.

Consider joining and becoming involved in climate action and climate justice groups, such as the Napa Sierra Club and Napa Climate Now. These groups clarify the various issues and steps needed to bring about the necessary political policy changes. Alternatively, you might join groups like Extinction Rebellion, which uses non-violent civil disobedience to pressure governments to act.

Educating and encouraging individuals and businesses to adopt energy-saving practices can significantly contribute to overall reductions in energy use.

• Both NASA and Climate.gov are reliable sources of information.
• Want to see energy flow charts for other countries, as well as California and other states? Check them out here. It's interesting to compare how different regions source and consume their energy.

Conclusion

Our current energy consumption patterns are heavily reliant on fossil fuels, leading to significant greenhouse gas emissions and environmental impact. While renewable energy sources are growing, they still represent a small fraction of our overall energy use. With a substantial amount of energy being wasted, there is a clear need for improved efficiency and smarter energy practices. By adopting a combination of technological innovations, efficiency improvements, and behavioral changes, we can reduce our energy consumption, minimize waste, and move towards a more sustainable and environmentally friendly energy future.

Please keep the discussion going. I would love to hear from you about your observations, questions, conclusions regarding this flow chart. Maybe I could use them in a follow up article. If interested, please email me, Nick Cheranich, at napavalleysierraclub@gmail.com