A system and method are provided to control hydronic systems having a plurality of sources, including at least one of an on-demand source, a semi-on-demand source, and an intermittent source that are fluidly or thermally coupled to a plurality of load zones. The hydronic system device obtains performance measurements for system components to provide system metrics, including failure diagnostics, energy capture, and usage optimization. The hydronic system device may also calculate British Thermal Units produced and used by the plurality of sources and loads to calculate incentives, including renewable energy credits.