Electrification is the process of powering by electricity and, in many contexts, the introduction of such power by changing over from an earlier power source. In the context of history of technology and economic development, electrification refers to the build-out of the electricity generation and electric power distribution systems. In the context of sustainable energy, electrification refers to the build-out of super grids and smart grids with distributed energy resources (such as energy storage) to accommodate the energy transition to renewable energy and the switch of end-uses to electricity.
The electrification of particular sectors of the economy, particularly out of context, is called by modified terms such as factory electrification, household electrification, rural electrification and railway electrification. In the context of sustainable energy, terms such as transport electrification (referring to electric vehicles) or heating electrification (referring to heat pumps powered with solar photovoltaics) are used. It may also apply to changing industrial processes, such as smelting, melting, separating or refining from coal or coke heating, or from chemical processes to some type of electric process such as electric arc furnace, electric induction or resistance heating, or electrolysis or electrolytic separating.
Benefits of electrification
Electrification was called "the greatest engineering achievement of the 20th Century" by the National Academy of Engineering, and it continues in both rich and poor countries.
Benefits of electric lighting Electric lighting is highly desirable. The light is much brighter than oil or gas lamps, and there is no soot. Although early electricity was very expensive compared to the 21st century, it was far cheaper and more convenient than oil or gas lighting. Electric lighting was so much safer than oil or gas that some companies were able to pay for the electricity with the insurance savings.
Pre-electric power In 1851, Charles Babbage stated: One of the inventions most important to a class of highly skilled workers (engineers) would be a small motive power—ranging perhaps from the force of from half a man to that of two horses, which might commence as well as cease its action at a moment's notice, require no expense of time for its management and be of modest cost both in original cost and in daily expense.
To be efficient, steam engines needed to be several hundred horsepower. Steam engines and boilers also required operators and maintenance. For these reasons the smallest commercial steam engines were about 2 horsepower. This was above the need for many small shops. Additionally, a small steam engine and boiler could cost as much as $7,000, while generating power using a living horse could be had for less than a tenth that price.Unskilled labor made approximately $1.25 per 10- to 12-hour day. Hunter and Bryant cite a letter from Benjamin Latrobe to John Stevens ca. 1814 giving the cost of two old blind horses used to power a mill at $20 and $14. A good dray horse cost $165.
One horsepower was often more than sufficient for many purposes. Man-powered tools, such as lathes, were common in many shops. Household sewing machines were powered with a foot treadle, unlike their line-shaft operated factory counterparts. Even dogs could be used to generate power, using a treadmill for tasks like churning butter.
In the late 19th century, specially designed power buildings leased space to small shops. These building supplied power to the tenants from a steam engine through line shafts. Electric motors were several times more efficient than small steam engines, owing to the efficiency of central generation and the lower losses due to friction. Electric motors were more efficient than human or animal power, with a conversion efficiency of 4–5% compared to 30% with coal power.
Economic impact of electrification
Electrification and economic growth are highly correlated. In economics, the efficiency of electrical generation has been shown to correlate with technological progress. In the U.S. from 1870 to 1880, each man-hour was provided with .55 hp. In 1950, each man-hour was provided with 5 hp, or a 2.8% annual increase, declining to 1.5% from 1930 to 1950. The period of electrification of factories and households from 1900 to 1940, was one of high productivity and economic growth. Most studies of electrification and electric grids focused on industrial core countries in Europe and the United States. Elsewhere, wired electricity was often carried on and through the circuits of colonial rule. Some historians and sociologists considered the interplay of colonial politics and the development of electric grids: in India, Yenda Srinivasa Rao showed that linguistics-based regional politics—not techno-geographical considerations—led to the creation of two separate grids; in colonial Zimbabwe (Rhodesia), Moses Chikowero showed that electrification was racially based and served the white settler community while excluding Africans; and in Mandate Palestine, Ronen Shamir argued that British electric concessions to a Zionist-owned company deepened the economic disparities between Arabs and Jews.
Current extent of electrification
While electrification of cities and homes has existed since the late 19th century, about 840 million people (mostly in Africa) had no access to grid electricity in 2017, down from 1.2 billion in 2010. Vast gains in electrification were seen in the 1970s and 1980s—from 49% of the world's population in 1970 to 76% in 1990. By the early 2010s, 81–83% of the world's population had access to electricity.
Electrification for sustainable energy
Clean energy is mostly generated in the form of electricity, such as renewable energy or nuclear power. Switching to these energy sources requires that end uses, such as transport and heating, be electrified for the world's energy systems to be sustainable. In the U.S. and Canada the use of heat pumps (HP) can be economic if powered with solar photovoltaic (PV) devices to offset propane heating in rural areas and natural gas heating in cities. A 2023 study investigated: (1) a residential natural gas-based heating system and grid electricity, (2) a residential natural gas-based heating system with PV to serve the electric load, (3) a residential HP system with grid electricity, and (4) a residential HP+PV system. It found that under typical inflation conditions, the lifecycle cost of natural gas and reversible, air-source heat pumps are nearly identical, which in part explains why heat pump sales have surpassed gas furnace sales in the U.S. for the first time during a period of high inflation.
With higher rates of inflation or lower PV capital costs, PV becomes a hedge against rising prices and encourages the adoption of heat pumps by also locking in both electricity and heating cost growth. The study concludes: "The real internal rate of return for such prosumer technologies is 20x greater than a long-term certificate of deposit, which demonstrates the additional value PV and HP technologies offer prosumers over comparably secure investment vehicles while making substantive reductions in carbon emissions." This approach can be improved by integrating a thermal battery into the heat pump+solar energy heating system.
Transport electrification
It is easier to sustainably produce electricity than it is to sustainably produce liquid fuels. Therefore, adoption of electric vehicles is a way to make transport more sustainable. Hydrogen vehicles may be an option for larger vehicles which have not yet been widely electrified, such as long distance lorries. While electric vehicle technology is relatively mature in road transport, electric shipping and aviation are still early in their development, hence sustainable liquid fuels may have a larger role to play in these sectors.
Heating electrification A large fraction of the world population cannot afford sufficient cooling for their homes. In addition to air conditioning, which requires electrification and additional power demand, passive building design and urban planning will be needed to ensure cooling needs are met in a sustainable way. Similarly, many households in the developing and developed world suffer from fuel poverty and cannot heat their houses enough. Existing heating practices are often polluting. A key sustainable solution to heating is electrification (heat pumps, or the less efficient electric heater). The IEA estimates that heat pumps currently provide only 5% of space and water heating requirements globally, but could provide over 90%. Use of ground source heat pumps not only reduces total annual energy loads associated with heating and cooling, it also flattens the electric demand curve by eliminating the extreme summer peak electric supply requirements. However, heat pumps and resistive heating alone will not be sufficient for the electrification of industrial heat. This because in several processes higher temperatures are required which cannot be achieved with these types of equipment. For example, for the production of ethylene via steam cracking, temperatures as high as 900 °C are required. Hence, drastically new processes are required. Nevertheless, power-to-heat is expected to be the first step in the electrification of the chemical industry with an expected large-scale implementation by 2025.
Some cities in the United States have started prohibiting gas hookups for new houses, with state laws passed and under consideration to either require electrification or prohibit local requirements. The UK government is experimenting with electrification for home heating to meet its climate goals. Ceramic and Induction heating for cooktops as well as industrial applications (for instance steam crackers) are examples of technologies that can be used to transition away from natural gas.
Energy resilience
Electricity is a "sticky" form of energy, in that it tends to stay in the continent or island where it is produced. It is also multi-sourced; if one source suffers a shortage, electricity can be produced from other sources, including renewable sources. As a result, in the long term it is a relatively resilient means of energy transmission. In the short term, because electricity must be supplied at the same moment it is consumed, it is somewhat unstable, compared to fuels that can be delivered and stored on-site. However, that can be mitigated by grid energy storage and distributed generation.
Managing variable energy sources
Solar and wind are variable renewable energy sources that supply electricity intermittently depending on the weather and the time of day. Most electrical grids were constructed for non-intermittent energy sources such as coal-fired power plants. As larger amounts of solar and wind energy are integrated into the grid, changes have to be made to the energy system to ensure that the supply of electricity is matched to demand. In 2019, these sources generated 8.5% of worldwide electricity, a share that has grown rapidly.