SVN solovelanet

SVN Solovelanet Global To run this motor continuously for about four hours, a 20 kWh battery pack is needed. To use the boat as many boaters do, i.e. returning or stopping in a marina each evening, and travelling up to 20-30 miles a day under motor power (let's keep in mind that we also have sails), the on-bo- ard battery pack is enough to provide the nee- ded run time. This can be easily recharged during night stops, by connecting it to shore power (it takes about six hours with a standard shore-side power source).The problem arises in case of very long voyages, when electric propulsion might be needed for more hours than the run time provided by the battery pack. To remedy this situation, the boat can be equip- ped with an energy recovery system, using the rotation of the propeller and of the electric motor when travelling under sail; with a three-bladed fi- xed propeller, at 6-7 knots under sail, the approxi- mate charging power is around 1.2-2 kW using the motor as a generator. Photovoltaic systems also come to our rescue, albeit with the limitations due to space, because we would need about 30 sqm of solar panels to keep under charge - or rechar- ge - a system with that power; and while a 12-me- tre catamaran has space enough, on a monohull of the same size, even if using bimini, sprayhood and deckhouse, it would be hard to fit more than 4 or 6 sqm, unless sacrificing accessibility of the deck and comfort on board. The experimental systems of photovoltaic sails have unfortunately not yet achieved the desired success and com- mercial feasibility.In any case, the installation of an auxiliary diesel generator for recharging could still be envisaged; it is an obvious contradiction and, in addition to the possibility of accessing all marine and lake protected areas, we would also lose the benefit of doing without the diesel tank and the consequent smells and emissions. Motors The present range of available electric motors for boats is as diversified as that of heat engines: available types include outboard, inboard with dri- ve shaft and inboard with sail drive motors, with the already mentioned feature of the rotatable sail drive. The design of an electric system starts from an estimate of the maximum power required, that has to be verified according to the conditions of use, such as racing, charter, and any challenging local conditions. L ong before Elon Musk started investing in Tesla, someone had already built electric outboard mo- tors for pleasure boats and more. In fact, the first sai- ling craft powered by an electric propulsion system was the ship Elektra, tested in 1886 by Werner von Siemens, whose factory had supplied the motor and accumulators. Elektra, that despite the name "ship" was just a little more than a wooden boat, should have been employed in the transport of passengers in Berlin, but because of the large size and weight of the accumulators and of their poor storage capacity, the use of steam ferries was eventually preferred. Since the first decades of the last century, electric outboard motors were launched on the market. Bu - ilt by prestigious manufacturers which then beca- me famous in the outboard motor industry, such as Evinrude, they never achieved much success, again because the accumulators were not suitable for sup- plying the required amount of energy. Between the end of the eighties and the beginning of the nineties, that problem was solved and this type of motors started to spread in the boating industry. At first electric motors were implemented mainly as submerged motors in small pleasure boats, but at present there are many types of motors available on the market, from outboards capable of supplying the equivalent of several dozens HP, to inboard drive shaft motors that can supply more than 100 HP. The future of electric systems is now outlined and it will not be many years before this type of propulsion system is fitted as standard by shipyards on sailbo - ats.At present, most electric motors are installed as retrofit, on boats where the engine needs to be replaced and an electric motor is preferred to a heat engine. On top, a drawing of the Elektra ship. Here aside, an electric outboard motor from the 1940s. History

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