Abstract: A method and system for determining fuel delivery frequency and volume for a combustion system is provided. A delivery history of fuel deliveries to a fuel combustion system fuel storage tank is collected. The heating degree days for each time period between deliveries is ascertained. The volume of fuel used per day between each delivery is then calculated. A relationship is then established between volume of fuel used per day and heating degree days per day, for the plurality of fuel deliveries for the combustion system. Desirably the relationship is established by plotting the volume used per day vs. heating degree days per day for the combustion system. A desired volume of fuel for the next delivery is chosen. The number of elapsed days from the last delivery and the elapsed number of heating degree days per day are tracked. Periodically, the expected fuel use is calculated using the relationship.

Abstract: A method and apparatus is provided for operation and optimization of boilers in a multiboiler heating plant. The apparatus includes a boiler selection means which is typically a computer which includes a fuel consumption profile for the boilers in the plant. A boiler controller is connected to the boiler selection means. An outdoor air temperature sensor is provided. In operation the fuel consumption profile of the various boilders at the current outdoor air temperature are compared and the boiler which will consume the least amount of fuel per degree day or other time unit is selected for operation.

Abstract: A multi-pane window with improved insulating qualities; comprising a plurality of transparent or translucent panes held in an essentially parallel, spaced-apart relationship by a frame. Between at least one pair of panes is a convection defeating means comprising an array of parallel slats or cells so designed as to prevent convection currents from developing in the space between the two panes. The convection defeating structures may have reflective surfaces so as to improve the collection and transmittance of the incident radiant energy. These same means may be used to control (increase or decrease) the transmittance of solar energy as well as to decouple the radiative transfer between the interior surfaces of the transparent panes.