On January 6, 2021, Beijing's meteorological station recorded the lowest temperature since 1966 -- minus 21 degrees Celsius. In fact, it's not just Beijing. Many cities in northern China have the lowest temperatures ever recorded in last 30 years.
In the cities like Rizhao and Dezhou in Shandong Province, where Kingpeng built large scaled glass greenhouses, a record low of -19 degrees Celsius was measured.
In these greenhouses, different heating method have been used. Greenhouses in Dezhou are heated by gas hot water boilers. and in Rizhao, the greenhouse heated by hot water drain from power station near by and also equiped with an oil boiler for suppliment.
In a greenhouse multi-way of heating is needed and It is important to have a stable temperatuere changing for crop growing. So, beside the boiler, double layer of curtain system have been used both in Dezhou and Rizhao.
We are glad to see, although the temperature drop to minus 19℃, the indoor temperature can still keep above 14℃ at nigh!