July was Hong Kong's hottest month ever. The heatwave caused us to use more energy, because so many people switched on their air conditioners.
To help the planet, green groups hope we can use more renewable energy.
One project is happening in Yim Tin Tsai, a little island in Sai Kung. The Jockey Club SolarCare Programme, run by CarbonCare InnoLab, promotes solar (sunlight) energy in Hong Kong. It wants young people to understand the importance of renewable energy.
The "Yim Tin Tsai Solar Power Day" had a solar invention workshop. It invited students to make a torch using solar energy.
"Families flocked to the island to see what solar energy can do," says Chong Chan-yau from CarbonCare InnoLab.
