Other popular event spaces taking part in the switch off include the National History Museum, 30 St Mary's Axe and the Royal Albert Hall.
This is the second year Earls Court and Olympia have taken part in the initiative.
"This is a fantastic project that unites landmarks across the globe. With our industry-leading sustainability programme we're delighted to support such a high-profile and worthy cause," said EC&O sustainability advisor Emma Wellman.
The initiative takes place just two weeks before Olympia plays host to UK Aware, the UK's leading green and ethical lifestyle show.
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