How far can I go?
The range of operation of Hybo 39 in its basic configuration (700Ah 48V Li ion batteries, 20Kw Motelectric engine) is decided basicaly by your urgence in reaching your destination.
The consumption of energy at 5kts gives you 14h (70 miles range).
Increasing or decreasing 1 knot redudes by half or doubles the time you can enjoy sailing (7 or 28 hours) and the range is reduced by 40% or increased a 60%.
So definitely, slow sailing is a 'must have' attitude!
In a sunny midsummer day, the solar panels can produce energy to charge around half of the batteries, so by the end of the day, if you harmonize production and consumption, you can enjoy a 50% more sailing time at the chosen speed.
You have many options to increase the range of operations, from installing a generator for specific purposes to install an wind generator, install more or bigger batteries, install an extended solar roof...
Electric, yes. Solar? Hybrid? Options open to autonomy
Boats for professional use, that carry out very specific and predictable tasks, can be completely electric with the option of plugging them into the grid, even though they may carry some solar panels on board that will increase the autonomy of the vessel.
For uses such as:
- day charter
- diving centres
- fishing outings
- bird-watching and sea animal-watching,
Equally, choosing a battery charger that allows for a particular speed in recharging the batteries, is an issue that is decided by balancing price and patience.
A set of 1000Ah batteries at 48V, which can be charged from the grid with the pre-installed chargers1, will provide 8-hour autonomy at the speed of 7-8 kts (for a 60-mile range). This time can be nearly doubled by decreasing the speed to 5-6 kts (which will increase the range to 90-120 miles). If it is a sunny day, the electricity produced by the panels (which have a power of 1200W) will provide additional recharge.
If more varied uses are required, then an optional 3KW generator can be installed on board, with a battery charger that can provide an autonomy of an additional 250 miles if fed with a 200 litre deposit (0.80 litres per nautical mile at a cruising speed of 7-8 kts).
The advantages of electric motorsThose who think that electric propulsion at sea is not reliable need to hear about the huge hybrid polar cruiser project, Roald Amundsen by Norwegian company Hurtigruten.
This is a vessel that, thanks to its diesel-electricity combination, saves 20% of the fuel that would be used by a boat with diesel motors that are directly connected to the propulsion. Of every 125 Tonnes that the same boat would consume with diesel-only propulsion, this diesel-electric system saves 25.
The reliability and robustness of electric motorization nowadays is right up there with diesel, and its increased simplicity of operation makes it become more and more accepted.
Other advantages are:
- The space required to install more compact electric propulsion machinery is much smaller than conventional systems
- The direct connection between the shaft of the propeller and the main motor reduces taxing efforts such as torsion and vibration
- There is more flexibility when it comes to installing the machinery
- It offers greater ease of use and redundancy
- Environmental benefits derive from lower consumption of fuel and emissions
- It reduces the cost of the life cycle as you have less fuel and maintenance costs
- Minimal waiting time for maintenance and services
- Increased comfort due to less vibration and noise
- Much better dynamic response from zero to top propulsion speed when compared with other propulsion systems
- Less time to go from forward to reverse gears, when compared with other propulsion systems
- Maximum torque available all along the range of propeller speeds
- Reduced spatial requirements for the shaft system
- Flexibility when choosing the speed of the diesel motor of the generator (in cases where there is a generator on board)
A charger? A generator? Why not 100% solar?
This issue always gives way to much discussion. Whenever someone is considering the idea of acquiring a solar vessel, and they hear about chargers, they think it is a contradiction. Let's break this down:
Depending on the use the boat will be given, it would be perfectly possble to function purely with the solar panels that are integrated in the basic design. Depending on the number of daily hours of use and the speed we desire, it is absolutely possible to reach a balance between the energy sourced by the panels and how much we consume. It is simply a question of calculating and adapting our use of the boat to the possibilities nature offers. This would be the most sustainable approach.
If we start to reflect on how we can care for the planet at a financial and material cost, with a philosophy that allows us to declare that we are responsible for the production and consumption of renewable energy when it comes to using our boat, we have a number of options available:
1. To make a big investment in panels and a structure that allow us to cruise the sea without the need for a charger. It is possible, as the WWFSolar did, to cross the Atlantic with no other energy source than solar panels – many of them, as can be seen in the photo. But we must
2. bear in mind that those panels, as they are set up horizontally, have a much lesser production (about 50% less) than if they were set towards the South at the optimal angle, which has to do with the latitude of our location. The weight of the scaffolding and the panels affect the boat's stability and require additional energy consumption for every mile. In the case of the WWFSolar, which crossed the Atlantic along the Equator, with the sun practically vertical at midday on the panels, the design was adequate. At our Mediterranean latitude, electricity production diminishes considerably.
3. To install on board the maximum amount of panels that can be integrated into the design of the boat, without unnecessary structures, knowing that these panels will never offer 100% production. We could invest in half the panels in option 1 being on land, with a more beneficial structure in order to place the panels on land in a more adequate position. While the boat is sailing, this land-based installation could provide energy to the port's installations and then recharge the boat when it returns to port.
4. To charge the vessel from the grid when you arrive at port, making sure that the supply comes from one of the existing renewable energy providers.
Finally, having a generator on board is perfectly possible, and we must say that the fuel consumption per mile, and therefore the CO2 emissions, are lower than the comsumption of a combustion motor covering the same route. The maintenance costs associated with a generator are also always lower than those of a traction motor.
We understand that many users may think that having a generator on board will offer them 'peace of mind', but we want to invite you to the experience of a calm navigation, that is simple, respectful and inexpensive, as can be provided by a vessel that is equipped with the minimum elements required to fulfill with its necessary functions.