CALGARY ― TC Energy Corp. gave the go ahead for construction of its US$8-billion Keystone XL Pipeline project on Tuesday, with a helping hand from the Alberta government.The company said Alberta has agreed to invest approximately US$1.1 billion as equity in the project, which substantially covers planned construction costs through the end of 2020.The remaining US$6.9 billion is expected to be funded through a combination of a US$4.2-billion project level credit facility to be fully guaranteed by the Alberta government and a US$2.7-billion investment by TC Energy.Watch: The oil price collapse could signal a huge deflationary shock to the economy.