t's official - according to the UN body responsible for tracking and tackling illegal drug production, the UNODC, almost 80% of all Afghanistan opium comes from the south-west of the country, including Helmand. But in the last 4 years Afghan opium growers there have all switched to using solar panels, and have effectively increased the world supply of heroin. Buying diesel to power their groundwater pumps used to be the farmers' biggest expense. For an upfront payment of US $5,000 they can buy an array of solar panels and an electric pump. Once it is installed, there are virtually no running costs. Many farms now get two harvests a year - some even get three. As a result, in 2019 opium production in the Helmand region reached a record 5,000 tonnes.