Singapore produces about 10 per cent of its food but as climate change and population growth threatens global food supplies, it aims to raise that to 30 per cent by 2030 under a plan known as 30-by-30. The challenge is space. “Whenever I talk about food security in Singapore, I tell folks ‘don’t think land – think space’. Because you can go upwards and sideways,” said Prof Paul Teng from NTU. A major hurdle for urban farmers are the expensive inputs like technology that put their products out of reach for many consumers, he added.