Energy Conservation

increasing efficiency of energy use and by avoiding the wastage of unnecessary use - this means the amount of energy needed for a taks is reduced

EFFICIENCY: measured the proportion of energy that actually achieved the desired activity WASTAGE: energy used for tasks that are thought to be unnecessary BUT measured on opinion

Low efficiency describes a gap between potential and actual output, while wastage is a physical manifestation of inefficiency e.g. a smaller vehicle may be much more efficient in its use of energy than a large vehicle yet driving it just for fun is still wasteful

TRANSPORT WHY? - as societies have developed and people have become more affluent, we have been able to travel more, afford global goods, and eat food imported over long distance - transport systems have become faster and more convenient and have a higher capacity for people and goods - transport infr and larger forms of transport have enabled industries to develop in a wider range of places away from the source of raw materials such as metal ores, limestone and coal

• faster, convenient, efficient transport of people and goods • materials to be transported from source to processing data • leisure and fun • goods to be transported from around the globe for us because we want them NOW! #AmazonPrime

• bulk transport • use longer vehicle route rather than lots of short journeys • use an economical vehicle • drive at optimum efficiency speed • reduce consumer needs for goods at inappropriate times or from unnecessarily far away - buy local

change can be successful if it doesn’t require habit change, it is more difficult if it relies on consumers chang ing their habits

• bulk transport - travel on bus/train or car share (number of passengers change the efficiency and practicality - must be mindful about where break even points are in terms of passenger miles/gallon e.g. London buses vs Penrith buses) • vehicle design • low embodied energy construction

• carrying larger loads on fewer vehicles is more energy efficient than using a large number of small ones • although more energy is used to move the larger vehicle, the larger load it can carry is likely to give it a greater overall efficiency

• FLEXIBILITY: of routes and destinations (e.g. the inconvenience of public transport compared to ‘door-to-door’ transport • TIME: the need for rapid transport of goods such as perishable foods • TAX: level of fuel tax

• energy from fuel = converted to kinetic energy to power the vehicle • if we can reduce the amount of fuel needed, and the fuel conversion is as efficient as possible, we can minimise the conversion of some energy into unwanted energy and maximise the amount of energy that can be used to push the vehicle forward

• aerodynamics/hydrodynamics • regenerative braking/KERS • reduced mass • wheel design • fuel combustion efficiency

reducing friction as the vehicle moves through the air/water reduces the amount of energy needed to propel it e.g. aerodynamic fairings on trucks/HGVs smooth the air flow over the cab and trailer

KERS = Kinetic Energy Recovery System • to slow a vehicle down, its kinetic energy must be converted into another energy form • conventional braking systems use friction to convert kinetic to heat, which is then lost to the atmosphere • more fuel must then be used to accelerate the vehicle again • RGS convert the kinetic energy that can be used/stored rather than wasted • road vehicles use a generator to convert kinetic energy to electricity which is stored as chem energy in a battery • this can be used to produce electricity that propels the vehicle using an electric motor e.g. hybrid cars have both a petrol engine and an electric motor which uses energy recovered during braking e.g. some trains recover energy while braking, they use a generator to slow the train but the electricity produced is fed back into the national grid via overhead cables

REDUCES FUEL CONSUMPTION, e.g……. • plastics instead of metals in cars where strength is unimportant, or carbon fibres which have a higher strength:weight ratio than most metals, e.g. Bugatti Mistral carbon fibre monocoque and body panels • steel alloys containing carbon, titanium and vanadium create high strength steel so that thinner, lighter body panels can be used • lighter neodymium speaker magnets replace ferrite ones • using high energy density batteries which have lower mass per unit of stored energy • lighter aluminium engine blocks replace cast iron ones • vehicles with rounded 3D surfaces have less surface area than angular corners, so less material needed • shorter cables are used in redesigning wiring systems and they are lighter • no-bleed aircraft engines have electric generators which power electric motors to control equip such as wing flaps/rudder. These are lighter than the pneumatic equipment used on most aircraft which run on pressurised ‘bleed’ air from the jet engine

• as air-filled or pneumatic tyres rotate, the weight of the vehicle squashes the tyre, changing its shape • when the vehicle moves, frictional heat is created by this continual change in the tyre shape and the movement of air inside the tyre • underinflated tyres lose even more energy • less energy is lost by using solid wheels, but these give a bumpy rise, unless vehicles using them run on rails e.g. Manchester trams, trains - steel wheels on rails give little resistance to rolling as they do not deform and change shape as they rotate e.g. buses with self-inflating tyre systems to ensure the pressure is always correct

• internal combustion engines are not able to burn 100% fuel they use • if combustion can become more efficient then less fuel is wasted Combustion efficiency can be improved through: - EFFICIENT EXHASUT GAS REMOVAL: having more valves per cylinder ensures the waste combustion gases are removed more completely so do not mix with the fuel - BETTER ENGINE TEMP CONTROL: e.g. using a thermostatically operated fan that only operates when the engine temp is above optimum - IGNITION CONTROL AND SERVICING: the timing of the ignition spark in petrol engines is important to burn fuel efficiently, so it is critical to ensure that engine ignition timing is always correct, e.g. through electronic ignition control of regular engine servicing

• traditional vehicle design focuses on the ease of component manu and assembly to create the vehicle • a newer concept is to design vehicles to minimise the env impacts of the disposal of vehicles when they are scrapped e.g. - use of recyclable materials where possible (e.g. recycled plastic/metal panels) - easy ID of components and their composition (e.g. being stamped with code numbers to identify composition) - easy dismantling and separation of components - use of reusable components for use in new vehicles - use of compostable/biodegradable materials for components that cannot be recycled (e.g. soy based foam for seats, hemp in panels)

• most energy used during a vehicle’s life is the energy to propel it but a significant amount is in its embodied energy • for a typical car, it is equivalent to its fuel consumption for 1.5 years • if the car is made with recycled materials, then its embodied energy will be much lower

• how a vehicle is driven affects fuel efficiency: TOO SLOW = a lot of energy is used just to run the engine rather than move the vehicle, TOO FAST = energy wasted through overcoming air resistance • therefore there is an optimum speed for efficient energy use, which for many cars is ~56mph • if a vehicle is unable to travel at its optimum speed (e.g. traffic congestion), then fuel will be wasted • we can reduce this and increase energy efficiency by installing automatic start/stop systems which cut out the engine when the vehicle is stationary, and also traffic management systems that encourage free traffic flow • driving smoothly (cruise control), in a higher gear, and avoiding sudden braking and accelerating will also improve fuel efficiency

• integrated transport system: road/rail/cycle etc • Active Traffic Management (ATM)/Smart Motorways • Driverless cars

• the most energy efficient method of transport is not necessarily the same for the whole length of th journey • schemes like park-and-ride, bicycle-carrying facilities on trains or integrated transport cards help to increase efficiency through ride sharing and reducing congestion e.g. TfL - tubes, buses, bikes, overground, taxis, boats, cable car, trams… Get a travelcard etc, or an oystercard

• variable speed limits can be used to prevent the serious congestion that causes delays and wastes energy • can use variable speed limit signs overhead • manages traffic by increasing capacity when numbers get very high - MAX EFFICIENCY • improve safety in bad weather or in congested conditions by adjusting traffic speed and flow • delays onset of congestion by increasing capacity, allowing smooth and efficient flow and real time info, trip times are more reliable • environmental benefits: decreased noise, emissions, fuel consumption • relatively low cost to install/maintain e.g. M42, M25

• hard shoulder conflict: increased crashes • space for gantry • public opposition • tech detects conditions, can be wrong. Automated deployment and vigilance from operators is manual to maximise benefit for drivers, but can be hard and human error, and everything relies on them