Category: Technology

23
May

RIVERSIMPLE ACCELERATES IN DUBAI

Riversimple has just returned from a two-month accelerator project in Dubai – an initiative that has seen the Rasa and our philosophy embraced by a completely different culture living in a much harsher environment. 

The timing wasn’t great, with 20 Beta test cars to get built in Wales, but when the Dubai Future Foundation, headed by Dubai’s Crown Prince, invited us to take part in the 4th Dubai Future Accelerators (DFA) programme, we jumped at the chance. We were sponsored  by a powerful government department: the Road and Transport Authority (RTA).

The view from the top of the Emirates Towers

Dubai is a place like no other. It laid its first modern brick in 1973 and is now a city state of 3 million thoroughly multicultural people. Furthermore, it continues to expand at a furious pace. Despite its terrible air quality, mad traffic issues and paradoxical desire to be environmentally friendly, there are 27,000 building projects on the go as we write and the skyscape is a sea of cranes.

The DFA is designed to enable businesses to develop technologies and proposals far quicker than would ever normally be the case. Companies taking part (37 in our ‘Cohort’, selected from 677 applicants) are hosted in the Government’s offices to allow for accelerated processes, hence the DFA’s tag-line: ‘pulling the future forward faster’.

The entrance to our office

Dubai is unashamedly determined to be quickest, boldest, biggest, highest, cleverest and altogether ‘the mostest’, not only among other Emirate states but also among all countries of the world. It also happens to be one of the hottest and dustiest places, humid and salty, so pretty tough for the Rasa. But that provides the perfect opportunity for us to ‘accelerate’ our technology development for much more extreme climates. We want to bring a Whole System Design approach to developing both a highly efficient cabin cooling system and  fuel cell cooling technologies. That done, the Rasa and its descendants could operate in a far wider, much warmer market.

So, for the past 8 weeks, a revolving team of Riversimple personnel have been in the DFA offices investigating how the RTA – and other independents – could embrace not only the hydrogen economy, but also our technology, circular economy business model, and a culture of ultimate efficiency.

We have met with around 80 different interested parties, exploring opportunities with R&D establishments, data specialists, blockchain experts, niche vehicle builders, financiers, transport companies (not least the RTA themselves), energy suppliers and distributors, entrepreneurs and developers, the EXPO 2020 organisers, and a host of national and federal government officials. The Welsh Government were there to support. It was a rollercoaster of dialogue and investigation and the result is an agreement with the RTA to progress our agenda, ultimately – we hope – building a dedicated Dubai-friendly prototype.

So, in the land of big cars with big wheels and big engines we are pleased to report that our championing of the hydrogen future, our circular economy model and all things Rasa have found synergy. And if small can be recognised as beautiful there, it can be anywhere.

Our grateful thanks are due to the Dubai Future Accelerators (in particular our Project Manager Faisal Kazim and Program Managers Karin Gabriel and Abdallah Kanaan), the Future team of the RTA (in particular the wonderfully enthusiastic and technically-savvy Mohamed Saleh Al Shareef), and our friends and advisors Kyle Weber, Dr Alessandro Zampieri and Mohamed and Abdulsalam Haykal).

22
Jun

GETTING REAL ABOUT AIR POLLUTION

We loved a recent tweet about Riversimple Rasa “I’d rather be cycling behind one of these.”

Cyclists on British roads sit on the frontline of traffic pollution.  It’s pretty unfair really, since they are not the ones responsible for that pollution.

Being able to travel from A to B is a fundamental part of modern life.  But then again breathing good quality air is pretty fundamental too!  The evolution of the car is a marvelous story, but our love affair with the combustion engine is slowly coming to an end.  Cleaner cars are on their way.  Just take a look around a busy parking lot and you will see how rapidly we are shifting to alternative fuels – cleaner, greener, better.

At Riversimple we are 100% with that cyclist.  None of us want to breathe in a cocktail of pollutants that include nitric oxide and nitrogen dioxide; carbon monoxide, and the heavy particulates associated with smog.

RASA TECHNOLOGY

As with all battery electric and fuel cell electric vehicles, the Rasa emits zero nasty emissions at the tail pipe, but a recent report published by Peter Achten and Victor Timmers of Edinburgh University highlights the problem of particulate emissions.  These emissions can come from the tyres and brakes as well as engines.  In fact, now that filters are so good, even diesel cars emit more particulates from tyres and brakes than from the engine.  According to the Achten/Timmers report, because many electric vehicles are heavier than combustion-engined cars, they emit higher levels of particulates.
The Riversimple answer is to go deeper into the design.REAR QUARTER SMOOTHED

The Rasa is strong but light – less than a third of the weight of the Toyota Mirai hydrogen fuel cell car.  This minimises any particulate emission from the tyres, because emissions are proportional to weight.  But even more significantly, the braking system for the Rasa is primarily electrical, rather than dependent on friction.

There are only two instances when the Rasa production model will rely upon friction brakes:

–           emergency stops, anything over 0.3g

–           below 5mph, when there is not enough braking torque

So the only regular release of brake particulates would be when braking at speeds below 5 mph.  However, as our engineers will tell you, the quantity of particulate release from friction braking is proportional to the kinetic energy of the car when you start braking.  At 5mph, the kinetic energy of the car is less than 0.7% that at 60mph.  In other words, particulates not a problem.

SURVIVAL OF THE FITTEST

In the wild, animals have a deep- seated ability to react to stimulus.  And in the longer term whole species can adapt to change through the process of natural selection.  It’s a simple, obvious thing – organisms that do not react, do not survive for long.

A similar ability to react is needed in industry.  Air pollution levels are unacceptable and some levels recorded are breaking regulations.  Changing the regulations, put there to protect our health, is no solution.

The businesses that are fittest for the times will survive and thrive.  Great news for people who breathe air.  Bad news for dirty, polluting industries with their heads still stuck in the sand.

06
Mar

BREAKING NEW GROUND – THE RASA POWERTRAIN

The powertrain describes the mechanism that generates power and propels a vehicle.  Over the years, standard linear powertrains – engine, gearbox, driveshafts to wheels – have been improved to make cars more reliable, more fuel efficient, less polluting, and so on. But fine tuning one particular system can only go so far, before each adjustment puts something else out of kilter.

The real step change happens when somebody decides to work up a completely fresh system. Thanks to modern technology, the scene has been set.  Enter somebody like Hugo Spowers.  Hugo is founder and Company Architect at Riversimple.  He is an Oxford University trained engineer who previously worked in the world of racing cars. We could also mention the bungee jumping or the piano on skis, but the focus of this blog post is the Rasa powertrain. Inspired by the Hypercar work of Amory Lovins at the Rocky Mountain Institute,  the Rasa powertrain has been designed to provide everything you need and nothing you don’t in terms of power – resulting in a car that can cruise along very efficiently on a tiny fuel requirement, but can also pack a big punch when asked to accelerate or climb a hill.

 Meet the Capacitors

At the heart of this car, is the hydrogen fuel cell. We describe how a fuel cell generates electrical energy from hydrogen here. But you can take the fuel cell to a whole new level with a bank of super-capacitors.

Super-capacitors in the Rasa

Super-capacitors in the Rasa

A capacitor is basically something that can store electrical energy. Capacitors also used to be known as condensers, used in a traditional ignition distributor. They consist of conductive plates separated by a non-conductive layer called the di-electric. When an electric current enters the capacitor, the di-electric stops the flow and a static charge builds up and is stored in an electric field between the plates. Batteries, in contrast, store electrical energy in a chemical form. This means that capacitors have some advantages over batteries: they can be charged and discharged very quickly and many times without wearing out.

But ordinary capacitors don’t hold very much charge; super-capacitors are an evolutionary leap. The prototype super-capacitors in the Rasa have a coating of charcoal and lithium ion to give them much greater capacity to hold energy – the supercap bank has a capacitance many times the capacitance of two concentric spheres the size of the planet.

Everything you need and nothing that you don’t

The unintended consequence of conventional powertrain architecture is that the engine is sized for peak acceleration, which is available all the time but is only needed for less than 10% of the time – so the car has to carry a heavy engine, and gearbox, that is 80% redundant for 90% of the time. In contrast, the Rasa powertrain will be able to recover energy that is traditionally wasted during braking, whilst allowing recaptured energy to flow precisely where it is needed, when it is needed, and for as long as is needed – but no more. There is no redundant capability, which otherwise translates into extra cost, weight and fuel consumption.

The Rasa's Network electric powertrain

The Rasa’s Network electric powertrain

This is pretty revolutionary, and is managed by purpose-designed Riversimple software – that’s the integrated brain of the car – ensuring that:

  • A small, light fuel cell maintains cruise
  • When braking, the motors in each wheel hub recover the kinetic energy and feed it into the bank of super-capacitors
  • This energy stored in the super-capacitors provides most of the power (approx. 80%) required for acceleration and hill climbing
  • The consequence is that cruise and acceleration are ‘de-coupled’ – no longer does better acceleration unavoidably increase the top speed

As a result, the Rasa is incredibly nippy with great acceleration (and that means fun to drive), whilst the size of fuel cell and fuel tank can be kept small and light. We call it a Network Electric system.

The powertrain needs further rigorous testing and adjusting – continuing with the Beta trials – but ultimately this, coupled with the overall lightness of the design, is where groundbreaking efficiencies are being made. We anticipate that the commercial Rasa will be more than 3 times as efficient as other fuel cell cars currently on the market.

 

 

14
Nov

What’s special about a Hydrogen Fuel Cell?

At Riversimple we think of hydrogen as an energy carrier not a fuel.

Petrol and diesel are primary fuels – you can dig them out of the ground – but if you think of hydrogen as a fuel you can make the wrong choices. In the past, some car companies invested a lot of time and money designing cars that burned hydrogen. Due to the quantity of gas required, the engineers also experimented with super-cooled liquid hydrogen, but there were numerous problems and the designs were dropped at a fairly early stage, mostly without reaching the market.

The fuel cell system being fitted into the Mark2 Alpha

The fuel cell system being fitted into the Mark2 Alpha

Our car does not burn hydrogen. Continue Reading..

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