Electricity just like any other product, has certain quality characteristics such as voltage level and tolerance, frequency, environmental performance, …But it also has very unique features.
The main characteristic of electricity is its high quality, and its resulting capability to serve practically any energy service (light, appliances, motion, electronics, heat) from a single system. The price to pay for this high quality is the conversion loss in the thermal power station, a loss that has been steadily decreasing over the past century, and is now approaching its thermodynamical limit. Serving all energy needs from a single system reduces cost of technical installations to the end-user. The capital becoming available could be used to invest in energy conservation (insulation), energy efficiency (class A+ appliances) or renewable generation.
Replacing electricity with less electricity
The efficiency of appliances to convert electricity into energy services is increasing steadily, and still has improvement potential. For example:
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Losses in refrigeration have been reduced historically by a factor 5, from the levels at the end of the 80’s to the best available technology in class A+ appliances (fig 3).
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Energy use for individual lighting applications can be reduced by a factor 5 or more . Modern lighting solutions are 50-100 times more efficient than candles.
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Distribution transformers, one of the most efficient machines ever designed by man, can still reduce losses by a factor 3-4 through the use of amorphous iron
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In motor driven systems (pumps, compressors, fans, washing machines, electric trains), it is possible to reduce losses by 30% on average.
Because of its high quality, using electricity instead other energy carriers can have a boosting effect to save primary energy and reduce greenhouse gas emissions, even when including conversion losses in power generation:
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The use of high speed electric trains instead of air transport reduces primary energy use per passenger.km by a factor 3 and CO2 emissions by a factor 4.
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Using electric trains instead of diesel trains reduces CO2 emissions by a factor 4 and primary energy use by a factor 2.
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Electric vehicles are twice as efficient as vehicles with internal combustion engines.
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Efficient heat pumps, drawing heat from the underground require 20-40 kWh of electricity to supply 100 kWh of heat; they typically reduce final energy demand for heating by at least a factor 3 and primary energy demand by at least 25%.
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With induction heaters for cooking, 90% of (final) energy goes in the pan, compared to 55% for gas-fired cooking.
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Modern high temperature heating solutions for industrial processes can in some cases save up to 80% of primary energy and up to 60% of CO2 emissions through their efficient use of primary energy.
At the next level, electricity – the only energy carrier that can power the digital economy – enables system-level efficiencies, eliminating or drastically reducing the need for certain energy services:
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Teleworking, reducing the need to commute
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Videoconferencing or webconferencing, reducing the need for travel
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Heating controls for building energy management, ensuring buildings are only heated when needed
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Dimmable lighting systems, ensuring exactly the right amount of light in the right place at the right time
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Process control technologies, especially in industry
