The present invention relates to power supply on board a sea-going vessel, such as a transport ship. The invention is especially adapted to provide renewable energy to auxiliary systems on board the vessel, such as to cooling or freezing containers transported by the vessel.
A seagoing vessel requires a substantial amount of energy. As a sea-going vessel can be connected to the electrical grid only when it is in port, this energy is generally provided by burning fossil fuels. It is estimated that the world's fleet of transport vessels account for about 2% of the total CO2 emissions of the world (https://www.iea.org/reports/international-shipping). It is therefore a great need to reduce this consumption.
It is known that reducing the speed of a vessel will reduce the fuel consumption substantially. For example a reduction of the speed from 24 knots to 21 knots will reduce the fuel consumption by 33% (https://transportgeography.org/contents/chapter4/transportation-and-energy/fuel-consumption-containerships/).
However, a slower speed means that the transport will take longer time. A longer time results in a greater total consumption of energy for auxiliary systems onboard the ship, such as for cooling the goods that the vessel is transporting. As a substantial part of the goods transport across the world takes place in areas where the temperature can get very high, even at the middle of the sea, there is a great need for controlling the temperature of the goods. Today, most goods are transported in containers. Special containers have been developed for providing a temperature-controlled environment inside of the container. This can be temperatures below freezing or temperatures above freezing but below a certain upper limit. Ships for transporting such containers are often termed reefers. The goods that are transported in such temperature-controlled containers are typically food products but may also range from flower to batteries.
The electricity for running the cooling or freezing containers comes today practically exclusively from generators driven by hydrocarbon-fuelled engines, running on hydrocarbons.
Some attempts have been made to harvest solar energy onboard boats. However, these solutions are intended for small boats. One such example is known from CN112532154A and CN112636683A. The publications describe a small, unmanned twin-hull boat having a platform extending between the hulls. On the platform a dedicated curved structure is arranged. The structure is equipped with a flexible solar panel that can be raised along the structure to collect sun energy and spooled onto a roll when it is not needed.
CN112960078A and CN211568242U show a small sailboat having a flexible solar panel glued to the deck.
None of the above solutions are intended for larges ships, such as a container ship.
The present invention has as an object to eliminate or at least reduce the need for operating such engines and make use of renewable energy in the form of solar power to supply the vessel with auxiliary energy.
By auxiliary energy is meant all types of energy on board the vessel that is not concerning propulsion. In addition to the supply of electricity to operate cooling and freezing containers, the auxiliary energy is used for lighting, heating, air conditioning, domestic appliances, control systems, elevators and other types of equipment and systems requiring electricity on board the vessel. It is the aim of the present invention to replace as much of this consumption as possible with solar energy.
Any surplus energy created by the present invention may of course be used for propulsion, such as when the vessel operates near a harbour, other populated areas or particularly vulnerable areas.
One or more of the above objectives are achieved by the features of the accompanying claims.
The invention will now be described, referring to the enclosed drawings, in which:
In the figures are shown an outer stack of containers 3. It should, however, be understood that stacks of containers may fill the space between the latching bridges 20. Each container 30 is secured to the latching bridges by known means.
The stacking of containers 30 and their attachment to the latching bridges 20 are not a part of the present invention. It is also possible to use the present invention on container ships without latching bridges.
At the ends of the latching bridges 20 are arranged rail columns 40 to support and guide rollable or foldable solar panels 50. It is convenient to attach these rail columns 40 to the latching bridges 20. If the ship has no latching bridges, a support structure for the rail columns 40 may be attached to the deck 10, such as by welding.
Each rail column 40 has two rails 42 attached thereto, one on each side of the rail column 40.
The upper roller 78 is adapted to travel within the second telescoping rail 41b. It is attached to an upper bar 51 to which an upper edge of the flexible solar panel 50 is attached. The bar 51 extends between two rail columns 40, as shown in
Rollers 79 similar to the upper roller 79 and bars 52 are arranged at spaced apart locations along the flexible solar panel 50 and the second telescopic rail 41b to support the flexible solar panel 50.
The flexible solar panel can be raised by turning a motor (not shown) arranged within the roll 60 to roll out the flexible solar panel. The counterweight 72 will then be allowed to move downwards within the column 40 and pull the wire 71 along.
The roll 60 may be driven by an electric motor that is housed within the roll 60 in a per se known manner.
When the flexible solar panel 50 is to be lowered and rolled up, the roll motor is reversed and rolls up the solar panel 50. The counterweight 72 is then lifted again to the top of the column 40.
The roll 60 may be driven by an electric motor that is housed within the roll 60 and is hence protected from sea spray. To roll up the solar panel 50, the motor is turned and pulls the solar panel 50 onto the roll 60. The rollers 79 that are attached to the bars 52 are one by one pulled out from the lower flared end 43 of the rail 42. When the solar panel 50 is raised again, the rollers 79 again enter the inside of the rail 42 through the flared portion 43. As will be understood, the flared portion will receive the rollers 79 even if they become somewhat skewed from the longitudinal axis of the rail 42.
As an alternative to rolling up the panels 50, they can be folded, such as into an open top container arranged below the panel 50
The solar panels of the present invention are primarily intended to be raised when there is a stack of containers arranged inward of the solar panel. The stack of containers will protect the solar panels from the impact and load of wind. When the ship has no deck load the solar panels may still be used if the wind speed is sufficiently low. It is convenient to provide a wind meter that is coupled to a control system that lowers the solar panels if the wind speed is too high for safe use, or if the wind comes from an inconvenient direction.
Sometimes it may be safe to use the solar panels on one side of the ship and not on the other. The control system may be set up with wind meters arranged at one or more places on the ship, so that individual solar panels may be raised or lowered depending on local wind variations.
At sea, the sunlight will be reflected from the sea and hit the solar panels. Consequently, the panels will be very effective, even at the shady side of the ship. It is, however, convenient to lower some of the solar panels when the need for power is lower than the total capacity of the solar panels. Excess power may be stored in battery modules on board the ship for use when there is too little sunlight or when the solar panels have to be lowered for protection.
The solar panels are themselves made of materials that are durable and can withstand both intensive sunlight and salt water. Rails, rollers, wire and other parts are conveniently made of durable plastic or stainless steel.
It may be advantageous to rinse the solar panels from time to time to remove residuals therefrom. This can be done while the ship is at port.
Number | Date | Country | Kind |
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20210789 | Jun 2021 | NO | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2022/065821 | 6/10/2022 | WO |