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Blog Post 26 March 2021

How Earth Hour can shine a spotlight on the climate emergency

Astronauts in the International Space Station may notice the Earth seems a little dimmer on 27 March 2021. Some might hope they see a complete blackout.

This Saturday evening marks the annual Earth Hour. Millions of people will turn off their lights at 8.30pm local time, to draw attention to climate change, food waste and many more environmental issues.

The Empire State Building, the Eiffel Tower and the Sydney Opera House are among more than 18,000 iconic buildings across the world that will take part in Earth Hour, turning city skylines dark to raise awareness of the climate emergency.

Though the circumstances this year are different due to the Covid-19 pandemic, there is still an opportunity to make an impact. This year, people from across the world are being invited to take part at home (by turning off their lights) and online, by joining in the first ever Earth Hour Virtual Spotlight.

The goal is to recreate the same unmissable sight seen around the world when lights go out online – taking over the social media feeds of millions around the world to shine a spotlight on the planet and our place within it.

Find out how to take part in this year’s Earth Hour Virtual Spotlight here.

What has Earth Hour achieved?

Later this year, world leaders with gather at climate conferences, including the much-anticipated COP26 event in Glasgow, to set the environmental agenda for the next decade and beyond. Critical decisions will be made on climate action and sustainable development, which will affect both people and the planet in the years ahead.

Since the first Earth Hour was held in 2007, the event has taken the climate emergency conversation from conferences to mainstream thinking. To list just a few of its achievements, Earth Hour has:

  • Created a 3.5 million hectare marine-protected area in Argentina.
  • Established a 2,700-hectare protected forest in Uganda.
  • Helped pass new legislation for the protection of seas and forests in Russia.
  • Initiated the planting of 20,000 mangrove seedlings in 13 cities in Indonesia.

How lighting can achieve more

With Earth Hour in mind, at Energy Saving Trust we are encouraging people to put their daily home and business lighting use under the spotlight.

The typical UK household has around 33 light bulbs, accounting for around 16% of your electricity bill. By using effective lighting controls (switching off unused lights) and energy efficient lighting (LEDs), lighting could drop to around 4-6% of the UK’s total electricity use.


Always turn the lights off

The quickest way to start saving is just remembering to turn lights off when you don’t need them. If you switch a light off when you leave the room, you will save more energy than it takes for the light to start up .

It’s also good practice to be aware of how many lights you have on in a room. If you have the main light on, do you need the lamp on too? By arranging light switches near the door, it makes it easier to remember to turn them off.

And if your home has external lights, use a sensor or timer so they’re only on when they need to be.


Change to LED bulbs

Switching from traditional halogen bulbs to a similarly bright LED can save you between £1 and £7 per year per bulb.

So, if the average household replaced all bulbs with LEDs, it would cost around £145 and save around £40 a year on bills, as well as reducing carbon emissions (CO2) by around 63kg each year.

If all 28 million homes in Britain switched to 100% LED bulbs, we could save 1.7 million tonnes of CO2 emissions annually.


LED performance

A good LED bulb should last between 15-25 years (15,000-25,000 hours) based on average use of being switched on for about 2.7 hours per day.

Different bulbs emit a different colour of light – it can vary from a warm yellow colour to the bluish-white colour of bright daylight.  Colour temperature is measured in Kelvin (K) and you just need to select the right bulb.

If you want a room to feel warm and cosy (bedroom or sitting room), look for an LED bulb that’s 2,700K. If you want a room to look bright and sleek (bathroom or kitchen), choose a 4,000K bulb.

See if you can make a difference by switching off your lights this Earth Hour to raise awareness of the urgent need to address the climate emergency.

Last updated: 25 March 2021