Where Does Electrical Energy Go To?

Electrical energy is the energy of moving electrons, typically generated by transforming kinetic or chemical energy into electricity using devices like generators, solar panels, fuel cells, or chemical batteries. It is a secondary energy source that is highly useful because it is easily transported and converted into other forms of energy like heat, light, or motion.

Most electrical energy is produced at large power plants using various energy sources. Fossil fuel plants burn coal, oil, or natural gas to boil water into steam that spins turbines connected to generators. Nuclear plants use the heat from nuclear fission reactions to convert water into steam. Hydroelectric plants use flowing water to turn turbines. Renewable sources like wind, solar, geothermal, and biomass can also be used to generate electricity.

The resulting electrical energy is distributed through transmission and distribution lines to homes, businesses, and industries. This versatile energy source can then be used immediately or converted into other types of energy on demand.

Table of Contents

Consumption by Sector

Electrical energy consumption can be broken down into three broad sectors: residential, commercial, and industrial. The residential sector encompasses energy used in private homes, such as for lighting, appliances, heating and cooling systems, electronics, etc. The commercial sector covers businesses, public buildings, and institutions. This includes energy used for lighting, heating and cooling, operating equipment, appliances, electronics, etc. Finally, the industrial sector comprises manufacturing, construction, mining, agriculture, and other heavy industries. This sector consumes electricity for operating machinery, heating, cooling, lighting, and running industrial processes.

According to U.S. Energy Information Administration (EIA) data, in 2019 the residential sector accounted for 38% of total U.S. electricity consumption, the commercial sector used 36%, and the industrial sector consumed 26%. However, the distribution varies significantly by region and country based on factors like climate, level of industrialization, and access to electricity. For example, industrial consumption can be well over 50% in rapidly industrializing countries like China and India. Tracking electricity use by sector provides insight into a nation’s economic activities and helps guide energy policy and planning.

Consumption by End Use

A significant portion of electrical energy is consumed powering devices and equipment in homes, businesses, and industries. The major end uses of electricity include:

Lighting – Lighting accounts for around 15% of global electricity consumption. Lighting is used in homes, businesses, streetlights, signs, and more.
Appliances – Major home appliances like refrigerators, washing machines, dryers, dishwashers, and ovens account for over 20% of home electricity use.
Electronics – Televisions, computers, monitors, game consoles, and other consumer electronics require significant electrical power when in use.

Motors – Electric motors are used extensively in industrial facilities and commercial buildings. Motors account for over 40% of global industrial electricity consumption.

In total, powering devices and equipment represents the largest single end use for electrical energy worldwide. Efficiency improvements in lighting, appliances, motors, and other end uses can significantly reduce electricity demand.

Transmission and Distribution Losses

A significant amount of generated electricity is lost during the transmission and distribution process before reaching end users. These losses can be categorized into technical losses and non-technical losses.

Technical losses are inherent to the transmission and distribution systems and include power dissipation in transmission lines, transformers, and other equipment. The amount of technical losses depends on the distance electricity has to travel, the equipment used, and the voltage level. Upgrading infrastructure and increasing voltage levels can help reduce technical losses.

Non-technical losses refer to electricity that is generated and enters the grid but does not result in revenue. This includes theft, defective meters, billing errors, and unmetered supply. Non-technical losses can account for a substantial percentage of total losses in some developing countries. Improving metering, billing, and law enforcement can reduce non-technical losses.

Overall, global transmission and distribution losses account for 8-15% of total electricity generation. Reducing these losses is an important priority to improve the efficiency and economics of the power sector.

Conversion Inefficiencies

A significant amount of electrical energy is lost during the process of generating and using electricity due to inherent inefficiencies in equipment. Power plants that burn coal, natural gas or biomass to generate electricity waste a substantial portion of the energy content of their fuel as heat during the combustion and electricity generation process. The average coal power plant is only around 33% efficient at converting the chemical energy in coal into electricity.

Equipment that uses electricity, such as appliances, also waste some of that energy as heat during operation due to mechanical and electrical inefficiencies. An incandescent light bulb, for example, converts only about 10% of the electricity it consumes into visible light—the rest is dissipated as heat. Energy efficiency improvements to power plants, transmission lines, and electrical equipment can help to reduce these conversion losses and get more useful energy out of the electricity generated.

Waste Heat

A significant amount of the electrical energy consumed ends up as waste heat. This refers to heat generated as a byproduct of electrical equipment and applications. For example, computers, appliances, machinery, and lighting fixtures all convert some electrical energy into heat during operation. This heat emanates from the device and warms the surrounding environment. While some waste heat is inevitable, it represents an energy loss. Improving equipment efficiency and insulating heated components can help minimize waste heat.

On a broader scale, electric power plants also generate enormous quantities of waste heat. Fossil fuel plants in particular tend to operate at relatively low efficiencies, with a majority of their fuel energy being released as heat. Cooling towers, lakes, or rivers are often used to dissipate this heat. Waste heat could potentially be captured and used for heating buildings or industrial processes. But there are technical and economic hurdles to overcome. Overall, waste heat represents a major use of electrical energy that provides little direct benefit beyond heating the atmosphere.

Energy Storage

A portion of electrical energy gets stored for later use in devices like batteries and capacitors. Rechargeable batteries in electric vehicles and electronics store electricity through chemical reactions. As the battery discharges to power the device, these chemical reactions release the stored energy. Capacitors and supercapacitors store electric charge on the surface of conductors that is later released to power devices. Utility companies use large battery banks to store electricity from renewable sources like solar and wind for release when production drops. Hydroelectric dams also act as large energy storage reservoirs by using excess electricity to pump water uphill into the dam which can later be released to generate electricity on demand.

Grid-scale energy storage allows surplus electricity generated during off-peak hours to be stored and dispatched during peak demand times. This helps balance electricity supply and demand. Batteries at the commercial and residential levels also enable electricity generated from rooftop solar panels to be stored and used at night. In all these cases, some portion of generated electricity is stored rather than directly consumed.

Exports

Electrical energy is often exported from areas of high generation to areas of high demand. Regions with excess electricity generation capacity can transmit that power to neighboring areas through interconnected grid networks. For example, Canada has abundant hydroelectric resources and exports electricity to U.S. states. The Pacific Northwest also exports hydropower to California. These exports allow areas like California to meet electricity demand without building as much local generation. Inter-regional electricity trading takes advantage of resource diversity and economies of scale in generation, reducing costs.

The amount of exported electricity depends on relative costs, transmission capacities between regions, seasonality, and demand fluctuations. For net exporting regions like Canada, electricity exports can account for a significant percentage of generation. The revenue from electricity exports also helps pay for generation assets. Overall, inter-regional electricity trading allows effective utilization of generation resources across interconnected networks.

Non-Quantifiable Uses

It is difficult to accurately account for all the ways electrical energy is used once it enters homes, businesses, and the economy. There are many small ways electricity is consumed that are hard to measure and quantify.

For example, many consumer electronics like TVs, cable boxes, and video game consoles draw power even when switched off or in standby mode. This standby power allows devices to power features like clock displays and remote controls. While it’s a small amount of power per device, with billions of electronics in homes, this standby power consumption starts to add up. However, it’s not typically metered or accounted for in energy consumption statistics.

Electricity used by small appliances and devices that are constantly plugged in and drawing power like phone and laptop chargers also goes unmeasured. Even though each charger only uses a few watts, billions of chargers plugged in around the world over the course of a year leads to substantial power consumption.

Conclusion

As we have seen, there are many ways in which electrical energy is ultimately consumed or lost after generation. The largest shares go towards residential, commercial and industrial sector usage, with lighting, heating, cooling, electronics and machinery being the primary end uses. Significant amounts are also lost in transmission, distribution and conversion inefficiencies inherent to our electrical grids and infrastructure. Additional electrical energy goes into powering exports, energy storage and other non-quantifiable uses. In summary, the electrical energy that is generated gets dispersed across a wide range of applications, processes and locations. Careful monitoring of exactly where it goes can help identify opportunities for efficiency improvements and more responsible usage.