U.K.-based power and transmission firm National Grid has set plans to invest $40 million in Clean Line Energy Partners, the Houston-based start-up proposing to build long, direct-current high power lines to move electricity from big wind farms in the central part of the U.S. to the country’s power-hungry population centers.



The investment in the firm by National Grid would follow Clean Line’s earlier backer, ZBI Ventures, a unit of Ziff Ventures, a private firm owned by the New York-based Ziff family.



The move by National Grid comes just a few months after Clean Line publicized plans to gather permits and rights-of-way for up to four new transmission lines at an estimated cost of $8 billion.



“National Grid shares Clean Line’s vision to help create the nation’s clean energy future by investing in transmission projects that facilitate the development of renewable energy resources,” the company said. National Grid Chief Executive Steve Holliday praised Clean Line’s “strong and capable” development team and its projects that promise to “advance the growth of renewable energy and the modernization of America’s energy infrastructure.”



The money will help Clean Line move ahead with development plans for its Plains & Eastern,  Grain Belt Express,  Rock Island line and the Centennial West power line projects.  National Grid will have the ability to acquire a “significant ownership stake” in Clean Line’s high voltage direct current projects. The company didn’t discuss any specific dollar figures on this front, however.



National Grid has already demonstrated a willingness to invest in wind. It’s inked an agreement to purchase 50% of the power from Cape Wind, the offshore wind farm planned for Horseshoe Shoal in Nantucket Sound, off  the coast of Massachusetts, for example.



While such projects are challenging, National Grid appears willing to take a chance that Clean Line will eventually hit pay dirt on one if not all four of its proposed transmission projects.



The U.S. offers one of the world’s best sources of wind power, combined with big pockets of demand located far away. For National Grid and Clean Line, it’s just a matter of connecting the dots through a long regulatory and funding process.