Screen-printable metallization pastes for forming thin oxide tunnel junctions on the back-side surface of solar cells are disclosed. Interdigitated metal contacts can be deposited on the oxide tunnel junctions to provide all-back metal contact to a solar cell.

A method for providing a fuel includes providing a partially purified biogas at a first processing site, where the partially purified biogas is produced by multiple biogas sources and/or from multiple feedstock sources. The partially purified biogas is compressed, fed to a mobile tank, and transported by vehicle to a second processing site. At the second processing site, which may also receive biogas from a plurality of biogas sources, the partially purified biogas is further processed to produce a fuel or fuel intermediate.

A heat exchange system includes a pump or compressor 100 that pressurizes a working fluid, a first heat exchanger 200 that receives the working fluid from the pump or compressor 100 and causes the working fluid to exchange heat with a first medium to decrease a temperature of the working fluid, first adjustment means 300 for receiving the working fluid from the first heat exchanger 200 and decreasing the temperature and a pressure of the working fluid, heat absorption means 400 for receiving the working fluid from the first adjustment means 300, second adjustment means 500 for receiving the working fluid from the heat absorption means 400, and a second heat exchanger 600 that receives the working fluid from the second adjustment means 500.

A liquefied gas system for capturing boil-off gas and reversibly adsorbing the boil-off gas on an adsorbent for later desorption and use comprises a first vessel for storing liquefied gas; a means for delivering gas from the first vessel to a system endpoint; a second vessel for storing boil-off gas emitted from the first vessel, the second vessel containing at least one adsorbent; a means for delivering boil-off gas from the first vessel to the second vessel, whereby the boil-off gas is reversibly stored on the at least one adsorbent; and a means for delivering the stored boil-off gas from the second vessel to the system endpoint. Also disclosed is a method of capturing boil-off gas from a liquefied gas system, wherein the captured boil-off gas is captured on an adsorbent for further use in the system. In one embodiment of the system and the method, the liquefied gas is liquid hydrogen, and the captured boil-off gas is used to power a hydrogen fuel cell.

A methane retention system is provided for reducing the amount of natural gas that is vented into the atmosphere during depressurization and maintenance of a natural gas compressor unit. Also provided are a method of depressurizing a natural gas compressor unit and a natural gas system, both of which include the methane retention system.

A liquefied gas unloading and deep evacuation system may more quickly, more efficiently and more completely unload liquefied gases from transport tanks, such as rail cars, into stationary storage tanks or into truck tanks. The system may utilize a two stage compressor, an electric motor, a variable frequency drive, a four way valve, a three way valve, a two way valve, a programmable logic controller based control system and pressure and temperature transmitters. The valving enables deep evacuation of the transport or supply tank to more completely empty the transport tank. The programmable logic controller and variable speed drive may be used to variably control the speed of the two stage compressor so that the system may be running as fast as possible during changes in ambient temperature and/or different stages of offloading the liquefied gases without exceeding the compressor's horsepower limit.

A storage tank system features a tank made of rigid material and an insulation assembly. The insulation assembly includes an inner membrane and an outer membrane wherein the inner membrane is located within the outer membrane and at least one of the inner membrane and outer membrane is made of a flexible material. An insulation medium is located in a space between the inner membrane and the outer membrane and a vacuum is applied to the space.

A method for providing a fuel includes providing a partially purified biogas at a first processing site, where the partially purified biogas is produced by multiple biogas sources and/or from multiple feedstock sources. The partially purified biogas is compressed, fed to a mobile tank, and transported by vehicle to a second processing site. At the second processing site, which may also receive biogas from a plurality of biogas sources, the partially purified biogas is further processed to produce a fuel or fuel intermediate.

A dewar for storing a cryogenic fluid features an inner vessel configured to store the cryogenic fluid and an outer vessel having an outer upper head and an outer lower head. The outer upper and lower heads are joined so as to define an interior chamber of the dewar. The inner vessel is positioned within the interior chamber of the outer vessel so that an insulation space, which is evacuated of air, is defined between the inner and outer vessels. A neck extends between the inner vessel and a central region of the outer upper head. The outer upper head and neck are configured so that the central region permanently deforms without breaking the neck when excessive shock loads are applied to the dewar.

An organic composite gas storage tank 100 comprises a hollow central portion 106 which is substantially cylindrical and formed integrally with first and second end portions 102, 104, and which defines a longitudinal tank axis 301. The first end portion comprises a hollow truncated conical region which meets the hollow central portion at a first end thereof, the outer and inner radii of the hollow truncated conical region decreasing in a direction along the longitudinal tank axis away from the hollow central portion. An organic fibre winding 107 extends at least between axial positions which coincide with the hollow truncated conical region of the first end portion and the hollow central portion respectively. The first end portion has a higher axial strength than that achievable for hemispherical end portion of a tank of the prior art.