(Photo/Iqilu.com)

Nightfall is drawing near. Workers wait for dinner beside the honeycomb briquette machines in courtyard No. 347, Renmin Road, Qingdao, east China's Shandong province. If traveled back to 10 years ago, the workers were usually busy making coal until late night.

During 1980s and 1990s, honeycomb briquette was the daily necessity in ordinary people's homes in Qingdao. People relied on it to cook meals and for heating.

Nowadays, central heating has replaced coal stoves for heating. Business of coal stores in the city is declining.