This month, Taiwan will hold a referendum that could have far-reaching effects on the world’s supply of semiconductors.

Taiwan is home to the world’s biggest chipmaker, Taiwan Semiconductor Manufacturing Co. (TSMC), and plays a crucial role in the global electronics supply chain. The logistical snarl caused by the pandemic showed how vital the island is to keeping auto and tech production lines running. Now a longer-term threat is emerging: energy supply.

Energy security and reliance on imported fossil fuels have long been key political issues for Taiwan that have become more inflammatory after the government committed to net-zero emissions by 2050. Only Australia is more dependent on coal power for its electricity among the world’s advanced economies.