Launched in Sydney in 2007, Earth Hour has become a global phenomenon.

An estimated 50 million to 100 million people worldwide will be switching off their lights to reduce global emissions and promote sustainable practices.

The council is doing its part to help reduce emissions with an aim to cut per capita emissions by 45 per cent by 2023.

To help with this goal, this year the council replaced more than 1650 fluorescent light tubes with energy-saving LEDs in its administration building at Speers Point.

Solar panels, with a combined capacity of 237 kilowatts, were installed at a number of sites and 21 energy-efficient heat pumps and solar hot water systems were installed in community facilities.

While Lake Macquarie City has a long history of being a coal-mining city, this image is changing. The city has the highest uptake of solar power in the Ausgrid residential network.

Last year electricity use decreased by 4 per cent across the city when compared with 2012-13.

Making small changes every day will help maintain a healthy environment for future generations and will help you save money.

■ Download the council's free Lake Macquarie Sustainable Living Guide from lakemac.com.au to learn how you can improve your energy efficiency, decrease water consumption and reduce waste.