Museum to add a $40-million Drawing Institute and an energy-efficient power plant to its Houston campus. The Menil Drawing Institute, west façade as seen from the Energy House. At a news conference in New York in mid-February Los Angeles-based architecture firm Johnston Marklee presented its design for the Menil Drawing Institute (MDI), a freestanding addition to the Menil Collection’s 30-acre campus in Houston. The 30,000-square-foot structure will sit south of the Menil’s main museum building from 1987 and its Cy Twombly Gallery from 1995, both designed by Renzo Piano. Johnston Marklee will also design an Energy House, which will serve