Deck saloon keelboats have caught up with modern motor cruisers offering anchorage and marina views, so it’s time for the latter to take another quantum  leap into the world of silent battery powered propulsion under the banner of ‘hybrid’. Alistair Vallance enjoys ultra quiet Clyde cruising on the Greenliner 36.

A STAR turn at Scotland’s ‘Royal’ Boat Show in October, the concept of alternative power sources on a modern 36ft motor yacht appeared to catch the imagination of the huge show crowd at Kip Marina.

For an extra £30,000 the option of cruising quietly under battery power with the fall back position of 18 knots under flat out diesel propulsion obviously added a new dimension to leisure sailing expectations.

Miles Stratton of Kip based Inspiration Marine, UK dealers for the Slovenia built Greenline range reported a big boat show interest in the dual power function and was keen that Yachting Life should put it to the test. One phone call was enough.

On a brilliant late October day we cast off from Kip and ventured onto the Clyde sun bathed in all its glory: A perfect setting to put the Greenline 36 hybrid through its paces.

But first, we needed answers to a couple of fuel burning questions raised by an earlier run through the Greenline brochure:

How could this new power saving concept be that frugal on diesel fuel usage? Did the unique hull design really flatten out rough waves?

Before stepping aboard we reminded ourselves of the fundamental diesel/electric power concept and solar charging capability that from Slovenia brought the world its first production built hybrid motor yacht back in 2010.

Main power plant is a Volvo Penta D3 220hp marine diesel allied to a 10kw electric motor with an integrated 7kw generator which takes power from 48 volt lithium polymer batteries, and at the end of the shaft is a mighty five blade prop.

The four, massive roof mounted photovoltaic panels feed the batteries at 1.3kw and when running diesel, the generator charges the batteries at 5kw.

But that’s not the whole story. Given half decent weather the panels charge continuously, building up a bank of battery power.

Shore power is not really needed, so that standard procedure is simply to cast off silently under electric power and, once clear of the marina, rev up the diesel to its maximum 18 knots for ten minutes or so, to put you firmly on cruising course and then it’s back to neutral, switch to electric power and throttle up to a silent five knots which, if the sun is shining will give 20 hours before a burst of diesel is needed to build up the power bank again.

Obviously the skipper requires to cast an eye on the instrumentation to check battery power availability.

We’re not suggesting that a filled 430 litre fuel tank would last the entire season…. or could it? It’s enough to turn red diesel green!

Keeping the environmentalists among us happy, the Greenline uses up to four times less fossil fuel in a year than a planing power boat and is completely emission free in electric mode.

Fine, but we were desperate to get afloat and find out the factual reality of how quiet is ‘silent electric running at five knots’.

How owner friendly is the deck, saloon and cabin layout and most important in our book, how stable is the super displacement hull?

As Miles Stratton explained; ‘The 36 has a different hull form to that of the Greenline 33 and 40 and behaves even better in choppy waters. Extensive tank testing was carried out and the recent sea trials of boat number one in Slovenia confirmed the sea keeping qualities.

‘The 36 does not need the stabiliser fins that the 33 and 40 have, although it does have a single centreline fin/skeg that provides better low speed manoeuvrability and protects the propeller and rudder.

‘Like the 33 and 40, the Greenline 36 has a reasonable air draft for cruising inland waters too.’

In addition, what we discovered later, was a downward slope at the aft underwater lip of the transom, that as good as negated any need for trim tab rocker buttons on the steering console.

As always, there are first impressions when stepping on board: Spacious aft cockpit, highly liveable saloon, totally different instrumentation console, heads below with Jack and Jill doors adjoining a twin berth stateroom, standing headroom throughout and all told we were mightily impressed.

A closer look revealed the top notch quality of all fittings from modern, robust cleats to a luxury fitted double sun bed on the foredeck that snaps down nicely for continued use even when faster cruising in double figures, with that ‘noisy’ diesel engine on!

It soon became patently obvious that the helmsman’s life on board the Greenline 36 will be starboard centric, thanks to the placement of a robust deck access door immediately to the right of the controls console.

The starboard deck too is worthy of positive comment. It’s a wide, safe side deck, well enclosed with plenty of hand holds, in stark contrast to the port side deck which in comparison is almost decorative.

No, this is a starboard action boat. Best to ask for a starboard pontoon berth in the marina. Although there is no side deck boarding gate built into the hull as in the Greenline 33, there is a huge hydraulically operated transom boarding platform which offers excellent pontoon access, or for bringing large amounts of goods aboard.

QUIET MURMUR

With the YL crew ensconced on the ‘36’ we flicked on the diesel engine and were surprised at the quiet murmur. Later, when we closely examined the spacious and well insulated engine room housing the Volvo D3, we understood why.

Armed at the console with both fore and aft thrusters, casting off and exiting Kip Marina allowed us to perform a master class in manoeuvrability. Confidence comes quickly on the Greenline 36.

Once out on the firth we cruised at 10 knots performing various exercises and if anything disappointed, it was the sluggishness of the steering wheel. Was it because it was saloon car size that we expected a car-like tightness? We felt that perhaps the hydraulics could do with a sharpen up.

Anyway, we soon learned to cope and inevitably we wanted to see what she could do flat out under diesel power. A quick look round thanks to 360° saloon vision, then hard to starboard and …nothing. The Greenline remained virtually flat, no heel, no roll. Hard to port, and more of the same.

Time to cut the gas now and go all electric, so it was back to neutral on the single throttle, a flick of the switch to battery power and we levered forward to five knots. The utter silence suggested a slower speed but the straight, frothing wake told a different story.

The Greenline 36 ticks all its performance boxes. We battery powered back to our marina berth accessing which, the bowthrusters proved their worth.

Neatly tied up, it was walkabout time after relaxing on the large aft deck, made even larger with an electronically lowered transom now providing access to a practical swimming ladder to starboard.

The patio door was opened, the glass wall at the galley removed and voila…interior space abounds. It’s a standard saloon layout for a motor yacht of her size, but it works well.

Seating for six, or at night with the table lowered, sleeping for two, with the owners cosily tucked up in their stateroom forward, and another two below.

This boat concept is so novel, inside and outside, that it’s best to let our pictures do the talking, however the galley does rate a special mention with all appliances at household power strength thanks to the boat’s 220 volt AC internal supply system. That means food mixers, microwave oven etc, can be totally portable.

And so we come to the price tag.

Miles Stratton was delighted that the Boat Show offer at the recent Kip event of a ‘free of charge’ navigation pack worth £8,124 was still available until early January.

This really is icing on a cake that is well endowed with extras.

Pricing is two-tiered: Firstly, the diesel powered-only version which is listed as £273,580. Go for the hybrid ‘package’ including the electric motor/generator plus lithium batteries and inverter, as tested, and you add another £29,575; total £303,155 including VAT, commissioned Clyde.

If there is a reluctance to go green and choose a higher powered diesel only propulsion, then the alternative is the 370hp Yanmar 8LV which offers 25 knots and really underlines the attributes of this J&J Design hull.