duffy london has developed a bamboo water taxi that combines cutting-edge solar technologies and one of the earth’s most practical natural materials. the hari pontoon is a new means of low-cost, fully sustainable water-based transportation that offers an environmentally friendly alternative to petrol-based boats. capable of harnessing the energy of the sun to transport up to 15 people or cargo loads, the simple and functional twin-hull design is built using local materials and processes, making it an affordable, versatile vessel ready for immediate production.


‘we wanted to make a sustainable watercraft that is extremely practical, spacious and safe,’ says duffy london founder, chris duffy. ‘our design philosophy throughout this project is to combine traditional materials and traditional craft techniques with cutting-edge solar and battery technology and blend this together using modern design and state of the art laser cut fixing components.’

duffy london
all images courtesy of duffy london



duffy london has designed hari pontoon predominantly from fast-growing bamboo, a naturally buoyant, widely available and cheap material. bamboo self-replicates at incredible speeds, with 100% natural fibres and resins combining to form a strong building material that has structural properties akin to modern fibreglass and carbon fibre composites. ‘to build itself, bamboo uses sunlight, water, and carbon dioxide,’ duffy continues. ‘we will use these properties to create a vessel that’s made from sunlight, powered by sunlight, lives on the water, and one that not only produces zero carbon, but also carbon captures.’

duffy london



efficiencies in solar capture and storage technology allow for a self-contained, near-zero maintenance power solution at a fraction of previous costs. the pontoon functions using a single, solar-powered electric motor to produce up to 60 horsepower, and a cruising speed of 8-10 knots. ‘we firmly believe that a vessel made of 98% bamboo 2% solar and battery technology will not only hold its own against modern vessels but in many ways can surpass them,’ duffy describes. ‘why use expensive, environmentally damaging materials that in many ways are not up to the standards of quality and structural integrity as bamboo, when we have an almost limitless and inexpensive supply of this material on our doorstep?’

duffy london



the project has been born from a design collaboration between the london-based studio and living waters, a new hotel planned for nusa penida in indonesia. as indonesia is the world’s largest island country, watercraft are an essential means of supporting local economies and linking communities. currently the vast majority of small boats in indonesia, and worldwide, are still fossil fuel-powered. the low maintenance costs and near-zero operational running costs of the hari pontoon offer potential customers a business viable, clean alternative. the expected carbon footprint of the watercraft would be fully paid off within six months of use.

duffy london



in an effort to overcome the initial costs in developing countries, the studio proposes a non-profit supply chain to allow business owners to purchase the hari pontoon with a low interest rate spanning multiple years. ‘our vision for this design is that it would go into a simplified and environmentally friendly mass production system,’ duffy explains. ‘by replacing many petrol-based vessels of similar size and usage, we could set up a non-profit to allow the vessels to be purchased at an extremely low rate of interest, lower than the monthly cost of fuel, to pay off the up-front costs over a number of years, and to provide a stable income for local people within their communities and to provide a far more environmentally friendly and environmentally conscious solution to everyday transport needs.’

duffy london develops the 'hari pontoon', a low-cost, solar-powered bamboo water taxi



while the vessel has been initially conceived for the island communities of indonesia, it can be used anywhere with sufficient amounts of sunlight, and — with continued improvements in solar technology — its application has no bounds. hari pontoon provides a clear vision for their future use, supporting travel across rural and urban environments worldwide.

duffy london develops the 'hari pontoon', a low-cost, solar-powered bamboo water taxi



product specifications: 


length: 7 meters
width: 3.5 meters
height: 3 meters


crew: 2
passengers: 15
max weight: 1800kg
max speed: 20 knots cruising speed: 8-10 knots


hull configuration: twin hull
hull material: bamboo composite
superstructure: bamboo composite


motors: 1
fuel type: lithium ion batteries
power: 60hp, 44kW
battery capacity: 33kWh
solar panel: CSUN325-72P
daily energy generation: 32kWh (theoretical max)


manufacturing costs:


boat: £3,000 GBP fixed price
solar panels: £1,200 GBP dropping by 3% per year on average
electrics and electric motors: £2,400 GBP dropping by 2% per year on average
batteries: £6,500 (in first year 2020) dropping by 10% per year on average