Posts Tagged ‘electric vehicles’

Self-Charging Cars

Back in 2010, Toyota developed a solar power system for the roofs of their Prius hybrid-electric vehicles (HEVs). The goal behind the initiative for Toyota was to see if a vehicle’s rooftop would provide enough solar power to charge the vehicle’s battery, providing drivers a few extra miles before the next charging session. According to Toyota, it was the company’s first steps towards producing a self-charging car. But the solar cells implemented into Toyota’s photovoltaic system provided just enough power to run auxiliary devices such as the power steering pump, ventilation fan, and air-conditioning compressor. This was due to the fact that the solar cells generated a capacity of only 50 watts.

Compare this with the design of the Lightyear One created by a startup company based in the Netherlands. Total peak output is 1.25kW which is enough power to provide anywhere between 20 – 45 miles of average range per day, according to Lightyear. Lowie Vermeersch created the design of the Lightyear One and an engineering firm based in Germany – Aachen – helped develop its integral 60-kWh battery system. The strategy, according to Lightyear’s chief technology officer, Arjo van der Ham, was their clean-sheet, systems-engineered approach.  This meant a propulsion motor at each wheel, lightweight materials, advanced aerodynamics, and enough sky-facing surface area to host about 1,000 photovoltaic cells. As Eric Wesoff of PV Magazine points out, the challenge to accomplishing the goals of aerodynamic efficiency and solar power efficiency lies in the design. He explains that you want a car that can both charge itself, which would require a broad area for the PV cells, yet remain aerodynamically efficient, which would require a narrow body design.

This is where Lightyear stayed true to its systems approach and the company believes it addressed this challenge in competing design goals. Lightyear believes it has met the challenge by integrating the motors with the suspension via a propulsion motor in each wheel and by making adjustments to the battery size. Lightyear also believes that they have now provided a solid architecture that other companies will use in the future as they push towards self-charging cars.

Taken from: www.sae.org

EV Battery Technology Shows Promise

A French company is currently developing a new energy storage device that may potentially see itself in electric vehicles. The company, called NAWA (short for NAno technology to fight against global Warming), is currently developing “ultra-capacitors” for use as storage devices that can be rapidly charged and discharged to match demands from electric vehicles. The ultra-capacitors are aiming to help some of the current limitations put on electric car batteries such as poor energy density and limitations on charging and discharging. The ultra-capacitors will be designed to be extremely efficient and may eventually have energy densities that rival current lithium celled batteries. Currently, the ultra-capacitors have superior energy density to current capacitor based energy storage and much better efficiency. NAWA is developing the ultra-capacitors using a state of the art technique that aligns series of carbon nanotubes in rows to allow the electrons to pass through the capacitor with limited resistance. A good analogy to the alignment of the nanotubes is to consider the uniform positioning of bristles on a toothbrush, providing a direct route for the electrons to travel through the ultra-capacitor. Two current issues with electric vehicles that are concerning for would-be consumers deal with the allowable range that electric vehicles are limited to, and how to charge the vehicle when the battery is drained. The new ultra-capacitors aim to help these two issues by allowing for current electric vehicle batteries to be lighter in weight, more efficient, and able to take a recharge more quickly. To deal with vehicle range limitations and rapid recharging, the carbon ultra-capacitors will supplement current lithium batteries with superior energy density and the ability to regenerate charge through vehicle decelerations, otherwise known as regenerative braking. Current regenerative braking is not very efficient, mostly because the battery cells cannot recouperate from such rapid recharging. New carbon ultra-capacitors will be able to accommodate the rapid recharging that occurs by regenerative braking, thus recollecting otherwise lost energy. Rapid charging will also be possible when using batteries enhanced with the new carbon ultra-capacitors, therefore reducing the amount of time spent waiting for an electric vehicle’s battery to be recharged. NAWA’s ultra-capacitors are still under development, but plans for testing in automotive applications is scheduled within the next five years. -taken from

European Union Develops Strict Emissions Standards

The European Union is developing new emissions standards that are aimed at decreasing pollution caused by motor vehicles. New emissions standards are rather widespread, however those being developed in Europe are some of the more stringent standards and many local municipalities are aiming at restricting pollution causing emissions even further. The typical effort behind these standards is to decrease the amount of diesel emissions caused by large long-haul trucks, vans, and buses. In fact, the European Union’s Mobility Package proposal calls for a 15 percent reduction of all CO2 emissions by 2025. Levels of emissions will be 30 percent lower than current 2021 goals by the year 2030. Specific targets for large vehicles, such as trucks and semis, are being developed currently and will be set in place sometime in 2018. Currently, emissions goals cover small passenger vehicles as well as larger vehicles such as delivery vans. The problem with this approach is that the emissions produced by smaller vehicles can be limited by current technology very easily, however emissions produced by larger vehicles is more difficult to control. Large vehicles that travel short trips, such as delivery vans in municipal areas, may be good candidates for electric drivetrains because the range traveled during normal deliveries is on the order of several miles or less. Electric drivetrains produce no emissions, however the range of electric vehicles is limited to the capacity of the batteries, which can be expensive to produce. For long-haul trucking, diesel will still be necessary for some time. Unfortunately, the cost of developing proper infrastructure, as well as unit development costs of batteries and electric drivetrains, will keep diesel as the front-runner for fueling long-range deliveries and cross-country shipping. Other transitional options away from diesel, such as natural gas or hydrogen power, are options that may be worth investigating to reduce emissions from long-range heavy equipment. -taken from