WEMO24-Compiled Report-Interactive compressed (002) 4154-7882-8116 v.1 - Flipbook - Page 84
Primary energy demand
is an outdated concept
EVs/LEDs and heat pumps are more
efficient
Example
Most people around the world are moving towards LED light
for homes and and offices. Figure 3 shows that LEDs are more
efficient and use 13% of the energy of a normal bulb. It also
shows that primary energy demand is the wrong way to look at
the low-carbon generation available to support the new, more
efficient lighting service.
Why Primary Demand creates the wrong measure of progress
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FIGURE 3
Finally, gas boilers have become much more efficient. For every
kilowatt hour (kWH) of energy you put in, 10% is waste heat.
However, with air source heat pumps, the latent energy in air
is used. So for for every kWh of energy you put in, you get
between 2 and 4 kWh of energy back. This is transformational
compared to gas boilers.
Let’s say you light your living room in rural India with a
75-watt normal lightbulb for five hours every night and
consume 135 kWh per year. If you power the bulb with
electricity from a coal plant with 35% efficiency and add10%
grid loss, then you create a primary energy demand of
435 kWh.
Source: The Better India News
The same amount of light can be delivered by a 10-watt
LED bulb. India is moving rapidly to solar, so if you run the
LED on local panels, you will consume 18 kWh per year and
you will have reduced your primary energy demand by 96%
and eliminated its CO2 emissions. However, you have still
delivered the same energy service.
WEMO 2024
Electric vehicles are also more efficient. For every dollar you
put in your diesel or petrol car, only 30 cents is used for moving
you forward—the rest is wasted heat. EVs provide the same
transportation service, but for every dollar you put in, 90 cents
is used for moving you forward.
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