Building Operating Management, July 2014, by Stefan Domby.
http://www.facilitiesnet.com/energyefficiency/article/Budget-For-Energy-Upgrades-Requires-Fully-Understanding-Real-Costs--15128

"Both in the private and public sectors, building owners and facility managers are focusing on managing energy costs more than ever before. But as we all know, you have to spend money to save money. It's important for facility managers to develop a plan to ensure that they do not run out of money before completion of the project and that the project budget is justified."