Powerdrive from Emerson Helps Wider Yachts Achieve 20% Fuel Savings


A luxury yacht manufacturer is using Powerdrive MD2 modular drives from Emerson as part of a unique power management system.



The application forms part of a bespoke system which delivers a 20% reduction in fuel consumption and allows the yacht to travel further between refuelling.



WIDER Srl, based in Castelvecchio di Monte Porzio, Italy, specialises in the design and construction of composite and aluminum pleasure craft with a strong focus on outstanding performance combined with low fuel consumption. The company’s Superyacht Division, where yachts up to 165ft are manufactured in aluminium, is located at the company’s satellite facility in nearby Ancona, which offers direct access to the sea.



The vessel, which features diesel-electric propulsion, is equipped with four MAN engines. Each engine is connected to an alternator to produce 350 kW of power that drives azimuthal pods.



“The power generated can be stored in lithium polymer battery banks, allowing the yacht to cruise completely under electric power and in total silence,” said Tilli Antonelli, founder and CEO of WIDER Srl. “Importantly, the propulsion system is managed by the proprietary Wider Management System (WMS), which was developed conjointly by WIDER’s engineering team and Emerson.”



Four variable speed generators deliver electrical power to the super yacht, with diesel engine speed controlled by the WMS featuring Powerdrive MD2 modular drives. This ensures the engines run at best efficiency in any cruising conditions to optimise overall consumption and maximise comfort for those sailing on the vessel. A DC variable voltage switchboard with a working range of 500-750V distributes the generated electrical power. Here, power levels are adapted instantly to the requirements of the system with the support of a battery pack. Of significant note is the fact that the super yacht can spend an entire night at anchor without ever having to start a generator as the entire hotel load can be run from the batteries, offering clear benefits in terms of fuel savings and comfort on board.



“Traditional yachts run the generators at a constant speed and produce a fixed output,” explained Mr Antonelli. “This is often too much or too little for the yacht’s needs, and as a result they are in frequent need of services and overhauls. The same is true of a yacht’s engines – these run at varying speeds according to requirements, consuming vast amounts of fuel and demanding regular attention and service.”



The diesel electric system on board the WIDER 150ft super yacht is different. By connecting MAN engines to alternators they can be employed as variable speed generators, producing only as much power as necessary at any given time. This results in greater efficiency from the engines – the engineering team at WIDER estimates fuel savings of up to 20% are achievable (depending on usage) compared with the same boat using traditional twin screw propulsion. At 11 knots it gives the super yacht a range of 4,200 nautical miles between refuels, a substantial distance for a vessel with a fuel capacity of 45,000 litres.



“The Powerdrive MD2 drives help make this possible, with power from the generators or the battery banks converted into what is needed at the time,” said Mr Antonelli. “This always assures the best performance in terms of consumption and efficiency – taking into account the overall demand for power on board.”



Powerdrive MD2 is a range of high power, compact and user-friendly modular drives. The combination of power modules and choice of cooling methods make it possible to achieve multiple optimised configurations: six-pulse, low frequency harmonics, regenerative or DC bus solution. Powerdrive MD2 provides high performance motor control, making it the ideal choice for any industrial or commercial variable speed application up to 2,800 kW.



A further benefit of the greater efficiency achieved on the WIDER super yacht through the use of variable speed generators and the power management system, is that it produces less noise and vibration. This results in greater enjoyment on board, which is the basis of WIDER’s philosophy to yachting, as well as longer intervals between maintenance.



“As a result of running efficiently, maintenance such as checking for exhaust build and dirt/grime on the generator valves is reduced,” said Mr Antonelli. “Additionally, although we have four generators, it is likely that most of the time only one or two will be used, together with the batteries, which means less hours/miles on the clock and less maintenance. It should even be possible to extend intervals between standard maintenance tasks such as oil and filter changes as the engine hours are managed more efficiently than on a standard yacht.”



Another important and beneficial feature of the design is that the Powerdrive MD2 drives convert the power from AC at the generators, to DC at the battery banks, and back to AC again when it powers the azimuthal pods or the appliances on board. This guarantees the greatest possible efficiency for the propulsion system, but also acts as a voltage stabiliser, thus eliminating voltage spikes that can be harmful to appliances. The battery banks are connected to a DC distribution bus that works at a nominal 675V DC, guaranteeing considerable power to the vessel but also allowing enormous flexibility in the way that the power is managed.



Everything is controlled by the power management system, which governs power generation, flow and storage. The number of generators that are running and their speed is checked constantly against the vessel’s requirements for safety, the demand for power and the state of the battery banks. A power management strategy can even be adopted to cater for specific requests from the yacht owner, such as noise reduction, high performance, zero emissions or night mode. Each profile can be selected manually.



“We are the first yacht builder in the world to offer luxury yachts in this size range with diesel-electric propulsion combined with azimuthal pods,” said Mr Antonelli. “In fact, the 150ft model is the first super yacht produced by WIDER and the entire range (including 125ft and 165ft models) will be powered by Emerson solutions.”



“Emerson is now a dedicated and trusted partner of WIDER and was instrumental in the development of the power management system,” added Mr Antonelli. “They recognised our needs and developed an innovative solution that provides us with a distinct competitive advantage.”



About Emerson:

Emerson (NYSE: EMR), based in St. Louis, Missouri (USA), is a global leader in bringing technology and engineering together to provide innovative solutions for customers in industrial, commercial, and consumer markets around the world. The company is comprised of five business segments: Process Management, Industrial Automation, Network Power, Climate Technologies, and Commercial Residential Solutions. Sales in fiscal 2014 were $24.5 billion. For more information, visit Emerson.com.



About Emerson Industrial Automation:

Emerson Industrial Automation (www.EmersonIndustrial.com), a business of Emerson, provides automation and power generation technologies and services to a wide range of industries. With its global capabilities and deep industry expertise, Emerson Industrial Automation is a trusted partner for products and solutions that increase machine performance, efficiency, reliability, and availability.

Its industry-leading brands include Appleton®, ASCO®, Branson®, Control Techniques, Leroy-Somer®, Numatics®, O-Z/Gedney, and SolaHD.



EMERSON INDUSTRIAL AUTOMATION

7078 Shady Oak Road

Eden Prairie

MN 55344-3505

Rob Kelly

Phone: +1 952 995 8173

rob.kelly@emerson.com



Emerson Industrial Automation, Control Techniques Ltd

Ty Rheoli,

79 Mochdre Industrial Estate

Newtown SY16 4LE

Chris Corfield

Phone: +44 1686 612996

Fax: +44 7818 522442

Chris.Corfield@Emerson.com  

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