In time or Free

In September 2017, Musk arranged a contract with the government of South Australia for Tesla Energy to install what would then be the world's largest lithium-ion battery pack, to help alleviate energy blackouts in the state. Musk arranged this on Twitter, with the guarantee that it would be installed in 100 days or would be free. This deadline was achieved and the resulting battery exceeded expected performance and returns, despite skepticism from Australian federal politicians.