Abstract: A system includes a plurality of capture hoods and a hood supporting unit. Each of the plurality of capture hoods has a hood portion and a connection portion. The connection portion is for connection to the hood supporting unit. The hood supporting unit is capable of connecting to just one of the plurality of capture hoods at a time. The hood portions of the plurality of capture hoods have different shapes. The connection portions of the plurality of capture hoods are identical so any one of the plurality of capture hoods can connect to the hood supporting unit.

Abstract: A system includes an intake, an exhaust, and an adjustable directing member. The intake is for taking in air, the exhaust is for exhausting air, and the adjustable directing member is positioned for directing exhaust air toward the intake. Another aspect is a system that includes a source of polluted air and an air cleaning system. The air cleaning system includes an intake, an exhaust, and a directing member. The intake is for taking in polluted air and the exhaust is for exhausting air. The directing member is for directing air from the exhaust toward the intake to provide an air screen for keeping the polluted air in the vicinity of the intake.

Abstract: A liquid heating system includes an electric current controller, a first container, and a second container. The first container includes a first liquid and a first electric heating system. The second container includes a second liquid and a second electric heating system. The electric current controller is connected to the first electric heating system and to the second electric heating system. The electric current controller is configured to automatically alternate between providing electric current to the first electric heating system and to the second electric heating system such that when the electric current controller is providing the current to the first electric heating system the electric current controller provides no electric current to the second electric heating system and when the electric current controller is providing the current to the second electric heating system the electric current controller provides no electric current to the first electric heating system.

Abstract: A liquid heating system includes an electric current controller, a first container, and a second container. The first container includes a first liquid and a first electric heating system. The second container includes a second liquid and a second electric heating system. The electric current controller is connected to the first electric heating system and to the second electric heating system. The electric current controller is configured to automatically alternate between providing electric current to the first electric heating system and to the second electric heating system such that when the electric current controller is providing the current to the first electric heating system the electric current controller provides no electric current to the second electric heating system and when the electric current controller is providing the current to the second electric heating system the electric current controller provides no electric current to the first electric heating system.

Abstract: A device for heating a liquid includes a tank, electrodes, and a conductive liquid. The tank holds the conductive liquid and the electrodes. The electrodes are connected to provide current flowing in the conductive liquid. The device also includes an electrolytic material supply vessel for holding the electrolytic material. The electrolytic material supply vessel is switchably connected for providing the electrolytic material to the tank. The device also includes an electrical parameter sensor for detecting a parameter of electrical energy dissipated in the conductive liquid. The device also includes a controller connected to automatically add the electrolytic material to the conductive liquid if the electrical parameter sensor detects the electrical parameter differing from a set point.

Abstract: A device for heating a liquid includes a tank, electrodes, and a conductive liquid. The tank holds the conductive liquid and the electrodes. The electrodes are connected to provide current flowing in the conductive liquid. The device also includes an electrolytic material supply vessel for holding the electrolytic material. The electrolytic material supply vessel is switchably connected for providing the electrolytic material to the tank. The device also includes an electrical parameter sensor for detecting a parameter of electrical energy dissipated in the conductive liquid. The device also includes a controller connected to automatically add the electrolytic material to the conductive liquid if the electrical parameter sensor detects the electrical parameter differing from a set point.