Energy Efficiency of the Gato Verde
The Gato Verde is the 42-foot catamaran run by Captain Todd Shuster that is used by the Beam Reach program for its boat-based hydroacoustics research of the Southern Resident orca population. The vessel employs several innovations pursuant to its mission of environmental stewardship, and in 2005 it became the first plug-in biodiesel-electric charter vessel on the West Coast. The dual 27-horsepower diesel engines were replaced by two electric motors, extra batteries, and a 10-KW biodiesel-powered generator. The batteries are charged both by the engine and the power harnessed by the sails. The use of wind by sailboats makes them a more sustainable vessel type in general, but the unique components of the Gato Verde distinguish it as especially robust and technologically advanced.
The truly distinctive feature of the Gato Verde is its hybrid-electric energy ystem. The motors are powered by the energy generated by the engine, which stands between the motors and the battery, and can therefore charge both. Energy efficiency of the engine is higher than it was under the previous conventional system, burning half as much fuel in the same amount of time. AC power takes the place of the generator when the catamaran is plugged into a terrestrial power source. The battery power is used to propel the boat as well as to provide electricity for the house system.
What makes the generator of the Gato Verde additionally sustainable is the use of biodiesel instead of petroleum-based fuel. Biodiesel is produced from any triglyceride-based oil, and while the level of carbon dioxide emitted per unit is 4.7% more by petroleum diesel, in fact the net emissions from biodiesel are less. A 1998 US government-sponsored study found that net CO2 emissions from biodiesel were 78 percent less than those of conventional diesel. The reason for this is that the oil used for the production of biodiesel is from a live plant, rather than a fossil fuel. In essence the CO2 is recycled back into plants that will be used to create more biodiesel: a closed carbon cycle.
While most catamarans are either sail or engine-powered, the Gato Verde employs both means of generating energy. When wind conditions allow for the sails to be employed for quicker navigation, the role of the motor switches to that of a mechanical generator, as the wind-derived electricity spins the propeller and charges the batteries in addition to moving the boat.
Beam Reach and the Gato Verde: Steps for Improvement Both the Beam Reach program itself as well as the Gato Verde can make changes to improve the sustainability of the lifestyle of the students on the boat as well as of the operation of the catamaran itself. Energy efficiency and conservation are principles that should be practiced not merely by using green technologies, but by being more conscientious about daily habits. A major issue that should continue to be discussed is that of diet and cooking on the boat. The amount of time and energy required for the cooking of certain dishes makes the frequency by which they are made something which should be considered. The propane tank had to be replaced very often during the program, and especially as the weather got cooler and hot water was constantly in demand, the galley cooking equipment was in almost constant use. Complicated dishes requiring the use of a lot of heat could be limited to just a few times a week, and simpler, less energy-intensive dishes could be served the rest of the time. This would both save propane energy as well as give the students extra time for other activities.
Electrical energy use on the boat is another matter to bear in mind. Much of the time on the boat that did not directly involve data collection was spent on data analysis. This involved several hours of computer use by multiple persons, requiring the use of the inverter to provide electrical energy for power. For multiple reasons the boat is not necessarily the best setting for comprehensive data analysis, not only for the power use but because it can also be a difficult setting for to focus in. An alternative could be that more boat time should be devoted to teaching topics relating to sustainability that were taught on land this year. This saves on technology usage and is also in the spirit of sustainability on the boat. A limited amount of time could be devoted to preliminary analysis of recordings each day, for such purposes as the separation of useless recordings from those with calls. Electricity shortage was a problem once during the program, an unfortunate occurrence that emphasized why it is so important to be aware of what it actually means to turn on the inverter and plug in electrical equipment. Liability insurance Washington
Finally, while the Gato Verde employs wind power, biofuel and hybrid-electric energy for power and energy, additional means of sustainable energy production can be added to increase efficiency further as well as to further the comfort of the students and instructors on the boat. Captain Shuster mentioned the possibility of adding photovoltaic cells to provide an additional power source, and given the amount of sunshine encountered while the boat was active during the program, PV cells could be a significant source of additional energy. The power of the sun could also be harnessed for heating, either by using thermal masses or solar water heating, the latter of which would also be a supplement to engine heat as a source of hot water on the boat. Sustainability is a central focus of the Beam Reach program, and through lessons on sustainability as well as via the lifestyle adopted on the boat, students can learn crucial concepts and are able to put them into perspective. Continuing to update the sustainability technology, daily habits and teaching techniques within the program can all help to further the mission of the school.