When a couple in their 70s in Nanjing, Jiangsu Province in east China, ordered food from a service center, a young man volunteered to deliver the food to their home. For the volunteer, the act is more than a charitable service.

For the half hour he spent on the delivery, he will have the same time credited to him. When he grows old and needs service, he can claim it for free. This is a new model of elderly care called time banking.

In Hangzhou, Zhejiang Province in east China, a senior care home has also come up with another new model. Young people can live in the home paying a low rent of 300 yuan ($42.7) per month provided they give at least 20 hours of service every month. The services include teaching the residents to use smartphones, watching TV with them or teaching them to paint, sing or dance.

Volunteer services that are mutually beneficial have become an important part of public senior care services under such models, lessening the pressure on the government to some extent.

Aging is becoming an increasingly serious problem in China. By the end of 2018, the number of people above 60 was 249 million, or 17.9 percent of the population. The cost of providing for the elderly is also increasing and there is a shortage of people working in the senior care sector. Volunteer services have therefore become an important solution to the elderly care problem.

(This is an edited excerpt of an article originally published in Beijing Youth Daily on November 21)