Its contract with NRG Energy reconsiders the ingredients for a power purchase agreement. : In the scheme of things, foodservice company Sysco’s new clean power arrangement with NRG Energy isn’t particularly large (just 25 megawatts), lengthy (10 years) or wordy (less than 10 contract pages). The simplicity and relatively modest size are precisely what makes the deal announced in early June — which covers three solar "gardens" in the Houston and Dallas area and came together in only six weeks — so notable.