falsos mitos

[Flyer]

tem algum interesse apesar de ser mais para a realidade americana.

http://www.sierraclub.org/electric-vehicles/myths.aspx

[ruimegas]

Electric Vehicles:
Myths vs. Reality

"Myth 1: Switching to an electric vehicle will just mean that the same amount of pollution comes from the electricity generation rather than from the tailpipe — I'll just be switching from oil to coal.
Reality: According to a range of studies, an electric car leads to 35 to 60% less carbon dioxide pollution from electricity than the CO2 pollution from the oil of a conventional car with an internal combustion engine.[1][2][3] In some areas, like many on the West Coast that rely largely on wind or hydro power, the emissions are significantly lower for EVs. And that's today. As we retire more coal plants and bring cleaner sources of power online, the emissions from electric vehicle charging drop even further. Additionally, in some areas, night-time charging will increase the opportunity to take advantage of wind power -- another way to reduce emissions.

A caveat to consider, according to some studies, is that when coal plants supply the majority of the power mix in a given area, electric vehicles may emit more CO2 and SO2 pollution than hybrid electric vehicles.[4] Learn where your electricity comes from, what plans your state or community has for shifting to renewables, and whether you have options for switching to greener power.

[IMG]http://www.sierraclub.org/electric-vehi ... n-leaf.jpg[/IMG]
The new all-electric Nissan Leaf. Photo by Darrell Clarke.

Myth 2: Plug-in cars will lead to the production of more coal and nuclear plants.
Reality: Even if the majority of drivers switched to electric, the existing electrical grid's off-peak/nighttime capacity for power generation is sufficient without building a single new power plant. Studies have shown that electric vehicle owners will largely charge their vehicles at night when there is plenty of capacity on the grid. In some areas, new "smart charging" allows you and the utility to set up a system by which you and other electricity users distribute the load evenly during charging so that the system is not overwhelmed by increased demand.

Myth 3: Electric car batteries pose a recycling problem.
Reality: Internal combustion engine vehicles use lead-acid batteries, and their recycle rate is about 98% in the US. The newer batteries for electric vehicles, such as those made of lithium-ion, include even more valuable and recyclable metals and will have a life well beyond the vehicle. In fact, a Belgian company plans to use Tesla Motor's electric vehicle battery pack material to produce an alloy it can further refine into cobalt, nickel, and other valuable metals as well as special grades of concrete. Technology will soon allow for EV batteries to store energy produced by solar or wind power.

Myth 4: My electricity bill will go way up.
Reality: While you'll spend more on electricity, the savings on gas will more than cover it. If you drive a pure battery electric vehicle 12,000 miles a year at current electricity rates (assuming $.12 per kilowatt hour though rates vary throughout the country), you'll pay about $389 per year for the electricity to charge your battery, but you'll save about $1200 in gas (assuming $3 per gallon, a 30 miles per gallon vehicle, and 12,000 miles driven). So $1200 minus $389 equals $811 in savings -a 68% reduction in fueling costs. Some utilities are offering EV owners lower off-peak/nighttime rates. The more we successfully advocate for these off-peak incentives, the lower your electricity payments will go.

Myth 5: Electric vehicles will just fail again like they did before.
Reality: Manufacturers are serious this time -- rolling out more than a dozen new plug-in models in the next couple of years, starting now. With higher gas prices and climate change worrying many consumers, stricter fuel economy standards for new vehicles required of auto manufacturers, and billions of public and corporate dollars being spent on an EV infrastructure and research in the US, EVs are here to stay.

Myth 6: My battery will run out of juice.
Reality: The majority of drivers in the US drive less than 35 miles each day, sufficient for a fully charged pure electric vehicle (most can go 80 to 140 miles on one charge), and an extended range electric vehicle (that drives about 35 miles on electric and then the gasoline power kicks in). Using a 220-volt outlet and charging station, a plug-in hybrid recharges in about 100 minutes, an extended range plug-in electric in about four hours, and a pure electric in six to eight hours. A regular 110-volt outlet will mean significantly longer charging times, but for plug-in hybrids and extended range electrics, this outlet may be sufficient. Most of the time, the battery will not be empty when you plug in, thus reducing charging time.

Most people will charge at home. However, some businesses and public entities are beginning to install 220-volt public chargers. Some are installing fast-charging stations along highways and in public places that can re-charge a car to 80% of battery capacity in less than 30 minutes.

Myth 7: Electric vehicles are much more expensive than traditional vehicles.
Reality: While the initial sticker price of EVs is higher than traditional vehicles, you need to do the math to account for a variety of factors. For individual consumers, there is currently a federal tax credit of up to $7,500 for the purchase of an electric vehicle, as well as a partial federal credit for the charging unit. Several states have additional tax credits on top of the federal ones. Additionally, the average EV driver will save more than $800 a year in fuel (the cost of electricity compared to gasoline). Due to a cleaner, more streamlined system under the hood, an EV may save the average driver about 46% in annual maintenance costs, according to one federal government study.[5]

Myth 8: Electric vehicles are only available in California.
Reality: While EVs are not yet available for purchase in every state, they are quickly becoming available in many. The fully electric Nissan Leaf is being sold to customers in California, Washington, Oregon, Arizona, and Tennessee. The Chevy Volt, an extended range plug-in hybrid electric vehicle, is currently being sold at select dealerships in California, Connecticut, Michigan, New Jersey, New York, Texas, and Washington, DC. Customers in nearly all states are expected to be able to purchase or lease a Leaf, Volt, or plug-in Toyota Prius by late 2011 or early 2012. The Tesla Roadster, a fully electric luxury sportscar, is available in several locations throughout the country. By 2012, many other models will become available nationwide, including the Ford Focus EV, Tesla Model S, and the Mitsubishi iMiev.

Myth 9: Charging an EV on solar power is a futuristic dream.
Reality: The technology to power your EV with solar power is already available. The investment in solar panels pays off faster when the solar power is not only replacing grid electricity, but replacing much more expensive gasoline. According to Plug In America, EVs typically travel three to four miles (or more) per kWh (kilowatt hour) of electricity. If you drive 12,000 miles per year, you will need 3,000-4,000 kWh. Depending on where you live, you will need a 1.5kW-3kW photovoltaic (PV) system to generate that much power for your vehicle using about 150 to 300 square feet of space on the roof of your home. According to SolarChargedDriving.org, for both vehicle and other home electricity needs, you will need about 7-10 kW of solar power in total on your roof. If your solar system is already in place but does not have enough panels for both home and vehicle charging needs, you may be able to buy a converter that can handle another "string;" micro inverter systems may be particularly good for this. Utility credits for the daytime solar power can offset the cost of charging the car at night. If solar PV isn't feasible at your home, find out if your utility offers a green energy option."

Em: http://www.sierraclub.org/electric-vehicles/myths.aspx

[jfreire]

Este mito número 1 tira-me do sério... Eu não percebo porque é que ninguém explica que estamos a comparar pêras com maças.

Estamos a comparar o CO2 de "tailpipe", com CO2 de well-to-wheel.

Para a comparação ser justa, tinha que se somar o CO2 emitido pelas plataformas petrolíferas, pelos petroleiros, pelas refinarias, pelos camiões cisterna e pelas bombas de gasolina (mais o CO2 dos caças bombardeiros, o CO2 dos fabricantes de bombas e de armas em geral, mas vá...).

Ou então somar 600g por Km às emissões de um ICE (número completamente inventado, mas não deve estar muito longe da realidade...)

Portanto, não interessa se é carvão ou energia solar. O CO2 "tailpipe" é sempre ZERO.

Posso dizer uma palavra feia? Posso? Então cá vai: PORRA! Pronto, eu avisei que este mito 1 tirava-me do sério...

Myth 1: Switching to an electric vehicle will just mean that the same amount of pollution comes from the electricity generation rather than from the tailpipe — I'll just be switching from oil to coal.
Reality: According to a range of studies, an electric car leads to 35 to 60% less carbon dioxide pollution from electricity than the CO2 pollution from the oil of a conventional car with an internal combustion engine.[1][2][3] In some areas, like many on the West Coast that rely largely on wind or hydro power, the emissions are significantly lower for EVs. And that's today. As we retire more coal plants and bring cleaner sources of power online, the emissions from electric vehicle charging drop even further. Additionally, in some areas, night-time charging will increase the opportunity to take advantage of wind power -- another way to reduce emissions.

A caveat to consider, according to some studies, is that when coal plants supply the majority of the power mix in a given area, electric vehicles may emit more CO2 and SO2 pollution than hybrid electric vehicles.[4] Learn where your electricity comes from, what plans your state or community has for shifting to renewables, and whether you have options for switching to greener power.

[mjr]

E cá em Portugal as emissões indiretas de CO2 de um VE são MUITO mais baixas do que qualquer ICE como já apresentei noutro tópico. Estamos a falar de menos de 50g CO2/km! E sem os enormes inconvenientes para o ambiente urbano de todas as emissões de partículas, óxidos de enxofre, etc dos ICE.

[RJSC]

E cá em Portugal as emissões indiretas de CO2 de um VE são MUITO mais baixas do que qualquer ICE como já apresentei noutro tópico. Estamos a falar de menos de 50g CO2/km! E sem os enormes inconvenientes para o ambiente urbano de todas as emissões de partículas, óxidos de enxofre, etc dos ICE.

Pois, além disso, nas centrais é fácil instalar filtros de partículas e catalisadores que têm dimensões impraticáveis para colocar em veículos, para além de que sem limitações de peso e espaço se podem construir motores muito mais eficientes.
Por exemplo, as centrais de gás natural de ciclo combinado atingem 60% de eficiência. Agora comparem isso com o motor de um carro a GPL. Talvez 27% com muita muita sorte...

[mjr]

27% rendimento de GPL? Só se for o pico de rendimento, em média deve estar abaixo dos 20%... Só com turbinas é possível chegar aos 40-60% de rendimento para gerar eletricidade. Curiosamente, apesar de ser uma tecnologia muito utilizada noutras aplicações, as turbinas nunca tiveram aplicação na produção em massa de VEs. O conceito do Volt era perfeito com uma turbina, que bem calibrada até poderia queimar gasolina, gasóleo, gás natural, etc... E com rendimentos sempre acima dos CI e com muito mais fiabilidade.