Consuming less will only get us so far—we also have to invent and invest our way out of the climate crisis. Luckily, the technology to remove carbon emissions from the economy is already happening. The energy intensity of the global economy, a measure of energy consumption per unit of gross domestic product, has fallen more than 32% since 1990.

But one key trend has reversed: The number of patents filed for climate change mitigation technologies more than doubled between 2005 and 2012, according to a recent analysis by researchers at the International Energy Agency (IEA) and the US Organisation for Economic Co-operation and Development (OECD). But since then, new patent filings for power, transport, buildings, manufacturing, and carbon capture and storage have plunged, bucking the general trend for global patents. New filings for carbon capture and storage and clean energy patents are down 44% and 29%, respectively, from their peaks, for example.

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