The Globe and Mail reports in its Wednesday edition that Deep Sky Corp., a Montreal-based start-up, is building its $50-million-plus Deep Sky Alpha project in Alberta to examine a range of direct-air-capture, or DAC, units from different vendors. The Globe's Jeffrey Jones writes that DAC has its supporters and detractors, and Deep Sky chief executive officer Alex Petre does not shy away from addressing the criticism, including the sheer number of facilities needed to remove massive volumes of greenhouse gas in the atmosphere. She sees it as one of many weapons required in the battle against climate change. Deep Sky has fired up three of its DAC units, marking the facility's formal opening. In the United States, expansion of the technology is up in the air as the Trump administration moves to cancel climate-related subsidies that were championed by former president Joe Biden. The $1.3-billion (U.S.) Stratos carbon-removal plant in Texas is being built by Occidental Petroleum using technology developed by B.C.-based Carbon Engineering. Occidental boss Vicky Hollub has stressed to U.S. President Donald Trump its potential enhanced oil recovery -- injecting the extracted CO2 into aging reservoirs to push out more crude.