Energy costs
When making purchasing decisions, we often focus on the amount of energy a product uses once bought. This is especially true for goods like TVs that have energy labels showing the efficiency and annual energy consumption through use.
But the most recent research we could find (from 2010) suggests that manufacturing a TV emits 300 kg CO2e.
By comparison, watching an average 40” TV emits around 52kg CO2e each year in the UK with our current electricity grid mix. That means it would take almost six years for use to equal manufacturing.
Production may have improved since 2010, but it is still likely that manufacturing is a substantial proportion of the lifetime carbon emissions of a TV.
This is without even mentioning the other environmental impacts of production: the huge amount of natural resources that are used, including 30 different minerals and lots of petrochemical-based plastics, the reliance on toxic chemicals, and the many issues with disposal…
Energy efficiency
Televisions are responsible for 4% of total electricity use in the home, and electricity use is itself only a fraction of home energy consumption overall, much more of which is heating. Still, energy
efficiency is always worth considering if you are going to buy a TV (whether second-hand or new).
Televisions are becoming more energy-efficient, helped in part by the introduction of the EU energy labelling scheme for televisions in 2010. TVs are rated A+++ to D.
With energy labels, it is tempting to read the headline energy efficiency class, the A or A+ rating, and then look no further. But the rating does not always correlate to how much energy your TV will actually use.
The overall energy use is affected by the size and features of the TV as well as its energy efficiency. As you might expect, the larger the screen the more energy required to power it.
Usefully, the EU energy label also shows the in-use power consumption in watts and the annual power consumption in kWh based on 4 hours’ usage per day.
It is this that is the important figure. The label also tells consumers whether the TV has a power button, enabling you to switch off the TV completely rather than leave it in ‘standby’ mode, which continues to use a small amount of energy.
If you want to make a choice based on energy consumption, the independent energy efficiency website www.sust-it.net lists over 300 televisions in terms of their in-use and standby running costs per day and per year, and users can sort by screen size and type. The Energy Saving Trust’s comparison site, www.toptenuk.org, shows the best performers for energy efficiency within different size brackets only.
The resolution race
As TVs become more energy-efficient, manufacturers are also racing to make them higher-res – undoing some of the good work when it comes to in-use energy consumption.
In recent years, manufacturers have moved from HD to Ultra-HD models. As a general rule, the higher resolution the TV (the more pixels used), the greater the energy consumption. 4K TVs – which have images 4000 pixels wide – consumed an average of 33% more energy than their HD predecessors at the point at which they were launched.
This year, manufacturers started offering 8K models – meaning they have again doubled the number of pixels on offer and again hiked the energy required.
Which screen?
There are several different screen types.
LEDs are the most energy-efficient screen, using roughly 20-30% less energy on average than an LCD of the same size. Plasmas are by far the least efficient, using almost twice as much power as an LCD and almost 3 times as much as an LED of the same size. For example:
Energy consumption by screen size and type
|
|
Power Consumption watts/hour |
|
Screen Size |
LED |
LCD |
Plasma |
30 inches |
50 |
60 |
150 |
50 inches |
100 |
150 |
300 |
Is it ever worth replacing your TV for a more energy-efficient model?
Even just from a carbon perspective, the answer is no. Televisions have become more energy-efficient over time.
But you’d have to wait 135 years if you replaced an average efficiency 40” TV from 2016 with an average efficiency 40” TV from 2019 before the energy-saving in use was more than the manufacturing carbon cost. (300 kg CO2e), based on the current carbon footprint of UK electricity (0.28307 kg CO2e per kWh).