News of the recent tug order for HaiSea Marine with Sanmar Shipyards also marks introduction of the ElectRA, Robert Allan Ltd’s (RAL) new range of battery electric tugs.

RAL's ElectRA fleet marks a significant development in battery electric tugs (RAL)

RAL's ElectRA fleet marks a significant development in battery electric tugs (RAL)

There is clearly no turning back now with development of alternative fuel tugs with RAL progressing the concept of battery power head-on and offering a range of five vessels between 21m and 28m in length and up to 70tbp.

The attraction is to significantly reduce or even eliminate exhaust emissions in ports and the HaiSea/LNG Canada order will see three ElectRA 2800 variant tugs ‘fuelled’ by clean hydroelectric power from the local grid, each vessel’s battery capacity of up to 6,102kWh allowing them ‘to perform a majority or even all missions on battery power alone’ realising the near complete elimination of CO2 and other potentially harmful exhaust emissions.

The range includes ElectRA 2100, 2300, 2500 and 2600-T variants, each offering a distinctly different take on battery electric propulsion. The 70tbp 2500 marque includes backup diesel gensets for fire-fighting and extended endurance but in a compact hullform with approximately 3,200kWh of battery power, RAL stating ‘these are still formidable battery electric tugs capable of a wide range of missions including escort.’

The ElectRA 2300 meanwhile recognises that battery tug operations will mostly take place in harbours with reduced requirements for overnight accommodation. By sacrificing some of this space, over 3,500kWh of battery capacity will be accommodated while maintaining some backup diesel generator capacity and a very capable bollard pull in excess of 60t.

The ElectRA 2100 is different again by eliminating the main gensets entirely along with associated space consuming diesel, exhaust, ventilation and cooling systems but retaining a small get-home generator in the deckhouse. This pure battery tug therefore allows a maximum installation in excess of 5,000kWh ‘designed to reduce costs associated with battery electric tugs to a minimum’ the 2100 model offers a bollard pull of 50t.

As the designation suggests, the ElectRA 2600-T is a tractor configuration compared to the previous ASD variants with nearly 4,000kWh batteries providing 70tbp and capable of fire-fighting and escort duties. The series can be customised to client’s requirements, described as critical to ensure the battery capacity meets the required energy needs while avoiding excessive investment compared to what is needed.

By Peter Barker