Month: 3월 2015

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Unclean at Any Speed

Electric cars don’t solve the automobile’s environmental problems

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Photo-illustration: Smalldog Imageworks; Photos: car, Transtock/Corbis; coal: Nolimitpictures/iStockphoto

Last summer, California highway police pulled over pop star Justin Bieber as he sped through Los Angeles in an attempt to shake the paparazzi. He was driving a hybrid electric car—not just any hybrid, mind you, but a chrome-plated Fisker Karma, a US $100 000 plug-in hybrid sports sedan he’d received as an 18th-birthday gift from his manager, Scooter Braun, and fellow singer Usher. During an on-camera surprise presentation, Braun remarked, “We wanted to make sure, since you love cars, that when you are on the road you are always looking environmentally friendly, and we decided to get you a car that would make you stand out a little bit.” Mission accomplished.

Bieber joins a growing list of celebrities, environmentalists, and politicians who are leveraging electric cars into green credentials. President Obama once dared to envision 1 million electric cars plying U.S. roads by 2015. London’s mayor, Boris Johnson, vibrated to the press over his born-again electric conversion after driving a Tesla Roadster, marveling how the American sports coupe produced “no more noxious vapours than a dandelion in an alpine meadow.” Meanwhile, environmentalists who once stood entirely against the proliferation of automobiles now champion subsidies for companies selling electric cars and tax credits for people buying them.

Two dozen governments around the world subsidize the purchase of electric vehicles. In Canada, for example, the governments of Ontario and Quebec pay drivers up to C $8500 to drive an electric car. The United Kingdom offers a £5000 Plug-in Car Grant. And the U.S. federal government provides up to $7500 in tax credits for people who buy plug-in electric vehicles, even though many of them are affluent enough not to need such help. (The average Chevy Volt owner, for example, has an income of $170 000 per year.)

Some states offer additional tax incentives. California brings the total credit up to $10 000, and Colorado to $13 500—more than the base price of a brand new Ford Fiesta. West Virginia offers the sweetest deal. The state’s mining interests are salivating at the possibility of shifting automotive transportation from petroleum over to coal. Residents can receive a total credit of up to $15 000 for an electric-car purchase and up to $10 000 toward the cost of a personal charging station.

There are other perks. Ten U.S. states open the high-occupancy lanes of their highways to electric cars, even if the car carries a lone driver. Numerous stores offer VIP parking for electric vehicles—and sometimes a free fill-up of electrons. Mayor Johnson even moved to relieve electric-car owners of the burden of London’s famed congestion fee.

Alas, these carrots can’t overcome the reality that the prices of electric cars are still very high—a reflection of the substantial material and fossil-fuel costs that accrue to the companies constructing them. And some taxpayers understandably feel cheated that these subsidies tend to go to the very rich. Amid all the hype and hyperbole, it’s time to look behind the curtain. Are electric cars really so green?

The idea of electrifying automobiles to get around their environmental shortcomings isn’t new. Twenty years ago, I myself built a hybrid electric car that could be plugged in or run on natural gas. It wasn’t very fast, and I’m pretty sure it wasn’t safe. But I was convinced that cars like mine would help reduce both pollution and fossil-fuel dependence.

I was wrong.

I’ve come to this conclusion after many years of studying environmental issues more deeply and taking note of some important questions we need to ask ourselves as concerned citizens. Mine is an unpopular stance, to be sure. The suggestive power of electric cars is a persuasive force—so persuasive that answering the seemingly simple question “Are electric cars indeed green?” quickly gets complicated.

As with most anything else, the answer depends on whom you ask. Dozens of think tanks and scientific organizations have ventured conclusions about the environmental friendliness of electric vehicles. Most are supportive, but a few are critical. For instance, Richard Pike of the Royal Society of Chemistry provocatively determined that electric cars, if widely adopted, stood to lower Britain’s carbon dioxide emissions by just 2 percent, given the U.K.’s electricity sources. Last year, a U.S. Congressional Budget Office study found that electric car subsidies “will result in little or no reduction in the total gasoline use and greenhouse-gas emissions of the nation’s vehicle fleet over the next several years.”

EV incentives map 
Source: Wikipedia
Generous EV Incentives: Governments around the world offer drivers various inducements to buy electric cars. The monetary incentives in western Europe, for example, include direct subsidies on vehicle purchases as well as certain tax exemptions. Some of these countries also provide the drivers of electric cars with free parking and other perks.

Others are more supportive, including the Union of Concerned Scientists. Its 2012 report [PDF] on the issue, titled “State of Charge,” notes that charging electric cars yields less CO2 than even the most efficient gasoline vehicles. The report’s senior editor, engineer Don Anair, concludes: “We are at a good point to clean up the grid and move to electric vehicles.”

Why is the assessment so mixed? Ultimately, it’s because this is not just about science. It’s about values, which inevitably shape what questions the researchers ask as well as what they choose to count and what they don’t. That’s true for many kinds of research, of course, but for electric cars, bias abounds, although it’s often not obvious to the casual observer.

To get a sense of how biases creep in, first follow the money. Most academic programs carrying out electric-car research receive funding from the auto industry. For instance, the Plug-in Hybrid and Electric Vehicle Research Center at the University of California, Davis, which describes itself as the “hub of collaboration and research on plug-in hybrid and electric vehicles for the State of California,” acknowledges on its website partnerships with BMW, Chrysler-Fiat, and Nissan, all of which are selling or developing electric and hybrid models. Stanford’s Global Climate & Energy Project, which publishes research on electric vehicles, has received more than $113 million from four firms: ExxonMobil, General Electric, Schlumberger, and Toyota. Georgetown University, MIT, the universities of Colorado, Delaware, and Michigan, and numerous other schools also accept corporate sponsorship for their electric-vehicle research.

I’m not suggesting that corporate sponsorship automatically leads people to massage their research data. But it can shape findings in more subtle ways. For one, it influences which studies get done and therefore which ones eventually receive media attention. After all, companies direct money to researchers who are asking the kinds of questions that stand to benefit their industry. An academic who is studying, say, car-free communities is less likely to receive corporate funding than a colleague who is engineering vehicle-charging stations.

Many of the researchers crafting electric-vehicle studies are eager proponents of the technology. An electric-vehicle report from Indiana University’s School of Environmental Affairs, for instance, was led by a former vice president of Ford. It reads like a set of public relations talking points and contains advertising recommendations for the electric-car industry (that it should manage customers’ expectations, to avoid a backlash from excessive claims). Even the esteemed Union of Concerned Scientists clad its electric-car report in romantic marketing imagery courtesy of Ford, General Motors, and Nissan, companies whose products it evaluates. Indeed, it’s very difficult to find researchers who are looking at the environmental merits of electric cars with a disinterested eye.

So how do you gauge the environmental effects of electric cars when the experts writing about them all seem to be unquestioned car enthusiasts? It’s tough. Another impediment to evaluating electric cars is that it’s difficult to compare the various vehicle-fueling options. It’s relatively easy to calculate the amount of energy required to charge a vehicle’s battery. It isn’t so straightforward, however, to compare a battery that’s been charged by electricity from a natural-gas-fired power plant with one that’s been charged using nuclear power. Natural gas requires burning, it produces CO2, and it often demands environmentally problematic methods to release it from the ground. Nuclear power yields hard-to-store wastes as well as proliferation and fallout risks. There’s no clear-cut way to compare those impacts. Focusing only on greenhouse gases, however important, misses much of the picture.

Manufacturers and marketing agencies exploit the fact that every power source carries its own unique portfolio of side effects to create the terms of discussion that best suit their needs. Electric-car makers like to point out, for instance, that their vehicles can be charged from renewable sources, such as solar energy. Even if that were possible to do on a large scale, manufacturing the vast number of photovoltaic cells required would have venomous side effects. Solar cells contain heavy metals, and their manufacturing releases greenhouse gases such as sulfur hexafluoride, which has 23 000 times as much global warming potential as CO2, according to the Intergovernmental Panel on Climate Change. What’s more, fossil fuels are burned in the extraction of the raw materials needed to make solar cells and wind turbines—and for their fabrication, assembly, and maintenance. The same is true for the redundant backup power plants they require. And even more fossil fuel is burned when all this equipment is decommissioned. Electric-car proponents eagerly embrace renewable energy as a scheme to power their machines, but they conveniently ignore the associated environmental repercussions.

Finally, most electric-car assessments analyze only the charging of the car. This is an important factor indeed. But a more rigorous analysis would consider the environmental impacts over the vehicle’s entire life cycle, from its construction through its operation and on to its eventual retirement at the junkyard.

One study attempted to paint a complete picture. Published by the National Academies in 2010 and overseen by two dozen of the United States’ leading scientists, it is perhaps the most comprehensive account of electric-car effects to date. Its findings are sobering.

whats in your EV? illustration 
Illustration: Bryan Christie Design
What’s in your EV? Don’t just think about the missing tailpipe. Manufacturing the specialized components that go into electric cars, such as the Nissan Leaf, has significant environmental costs.

It’s worth noting that this investigation was commissioned by the U.S. Congress and therefore funded entirely with public, not corporate, money. As with many earlier studies, it found that operating an electric car was less damaging than refueling a gasoline-powered one. It isn’t that simple, however, according to Maureen Cropper, the report committee’s vice chair and a professor of economics at the University of Maryland. “Whether we are talking about a conventional gasoline-powered automobile, an electric vehicle, or a hybrid, most of the damages are actually coming from stages other than just the driving of the vehicle,” she points out.

Part of the impact arises from manufacturing. Because battery packs are heavy (the battery accounts for more than a third of the weight of the Tesla Roadster, for example), manufacturers work to lighten the rest of the vehicle. As a result, electric car components contain many lightweight materials that are energy intensive to produce and process—carbon composites and aluminum in particular. Electric motors and batteries add to the energy of electric-car manufacture.

In addition, the magnets in the motors of some electric vehicles contain rare earth metals. Curiously, these metals are not as rare as their name might suggest. They are, however, sprinkled thinly across the globe, making their extraction uneconomical in most places. In a study released last year, a group of MIT researchers calculated that global mining of two rare earth metals, neodymium and dysprosium, would need to increase 700 percent and 2600 percent, respectively, over the next 25 years to keep pace with various green-tech plans. Complicating matters is the fact that China, the world’s leading producer of rare earths, has been attempting to restrict its exports of late. Substitute strategies exist, but deploying them introduces trade-offs in efficiency or cost.

The materials used in batteries are no less burdensome to the environment, the MIT study noted. Compounds such as lithium, copper, and nickel must be coaxed from the earth and processed in ways that demand energy and can release toxic wastes. And in regions with poor regulations, mineral extraction can extend risks beyond just the workers directly involved. Surrounding populations may be exposed to toxic substances through air and groundwater contamination.

At the end of their useful lives, batteries can also pose a problem. If recycled properly, the compounds are rather benign—although not something you’d want to spread on a bagel. But handled improperly, disposed batteries can release toxic chemicals. Such factors are difficult to measure, though, which is why they are often left out of studies on electric-car impacts.

The National Academies’ assessment didn’t ignore those difficult-to-measure realities. It drew together the effects of vehicle construction, fuel extraction, refining, emissions, and other factors. In a gut punch to electric-car advocates, it concluded that the vehicles’ lifetime health and environmental damages (excluding long-term climatic effects) are actually greater than those of gasoline-powered cars. Indeed, the study found that an electric car is likely worse than a car fueled exclusively by gasoline derived from Canadian tar sands!

As for greenhouse-gas emissions and their influence on future climate, the researchers didn’t ignore those either. The investigators, like many others who have probed this issue, found that electric vehicles generally produce fewer of these emissions than their gasoline- or diesel-fueled counterparts—but only marginally so when full life-cycle effects are accounted for. The lifetime difference in greenhouse-gas emissions between vehicles powered by batteries and those powered by low-sulfur diesel, for example, was hardly discernible.

The National Academies’ study stood out for its comprehensiveness, but it’s not the only one to make such grim assessments. A Norwegian study published last October in the Journal of Industrial Ecology compared life-cycle impacts of electric vehicles. The researchers considered acid rain, airborne particulates, water pollution, smog, and toxicity to humans, as well as depletion of fossil fuel and mineral resources. According to coauthor Anders Stromman, “electric vehicles consistently perform worse or on par with modern internal combustion engine vehicles, despite virtually zero direct emissions during operation.”

Earlier last year, investigators from the University of Tennessee studied five vehicle types in 34 Chinese cities and came to a similar conclusion. These researchers focused on health impacts from emissions and particulate matter such as airborne acids, organic chemicals, metals, and dust particles. For a conventional vehicle, these are worst in urban areas, whereas the emissions associated with electric vehicles are concentrated in the less populated regions surrounding China’s mostly coal-fired power stations. Even when this difference of exposure was taken into account, however, the total negative health consequences of electric vehicles in China exceeded those of conventional vehicles.

North American power station emissions also largely occur outside of urban areas, as do the damaging consequences of nuclear- and fossil-fuel extraction. And that leads to some critical questions. Do electric cars simply move pollution from upper-middle-class communities in Beverly Hills and Virginia Beach to poor communities in the backwaters of West Virginia and the nation’s industrial exurbs? Are electric cars a sleight of hand that allows peace of mind for those who are already comfortable at the expense of intensifying asthma, heart problems, and radiation risks among the poor and politically disconnected?

they all pollute chart 
Source: National Academies Press
They all pollute: Even assuming 2030 vehicle technology and grid enhancements, the National Academies concluded that the health and nonclimate damage from electric cars would still exceed the damage from conventional fueling options.

The hope, of course, is that electric-car technology and power grids will improve and become cleaner over time. Modern electric-car technology is still quite young, so it should get much better. But don’t expect batteries, solar cells, and other clean-energy technologies to ride a Moore’s Law–like curve of exponential development. Rather, they’ll experience asymptotic growth toward some ultimate efficiency ceiling. When the National Academies researchers projected technology advancements and improvement to the U.S. electrical grid out to 2030, they still found no benefit to driving an electric vehicle.

If those estimates are correct, the sorcery surrounding electric cars stands to worsen public health and the environment rather than the intended opposite. But even if the researchers are wrong, there is a more fundamental illusion at work on the electric-car stage.

All of the aforementioned studies compare electric vehicles with petroleum-powered ones. In doing so, their findings draw attention away from the broad array of transportation options available—such as walking, bicycling, and using mass transit.

There’s no doubt that gasoline- and diesel-fueled cars are expensive and dirty. Road accidents kill tens of thousands of people annually in the United States alone and injure countless more. Using these kinds of vehicles as a standard against which to judge another technology sets a remarkably low bar. Even if electric cars someday clear that bar, how will they stack up against other alternatives?

For instance, if policymakers wish to reduce urban smog, they might note that vehicle pollution follows the Pareto principle, or 80-20 rule. Some 80 percent of tailpipe pollutants flow from just 20 percent of vehicles on the road—those with incomplete combustion. Using engineering and remote monitoring stations, communities could identify those cars and force them into the shop. That would be far less expensive and more effective than subsidizing a fleet of electric cars.

If legislators truly wish to reduce fossil-fuel dependence, they could prioritize the transition to pedestrian- and bike-friendly neighborhoods. That won’t be easy everywhere—even less so where the focus is on electric cars. Studies from the National Academies point to better land-use planning to reduce suburban sprawl and, most important, fuel taxes to reduce petroleum dependence. Following that prescription would solve many problems that a proliferation of electric cars could not begin to address—including automotive injuries, deaths, and the frustrations of being stuck in traffic.

Upon closer consideration, moving from petroleum-fueled vehicles to electric cars begins to look more and more like shifting from one brand of cigarettes to another. We wouldn’t expect doctors to endorse such a thing. Should environmentally minded people really revere electric cars? Perhaps we should look beyond the shiny gadgets now being offered and revisit some less sexy but potent options—smog reduction, bike lanes, energy taxes, and land-use changes to start. Let’s not be seduced by high-tech illusions.

This article originally appeared in print as “Unclean at Any Speed.”

http://spectrum.ieee.org/energy/renewables/unclean-at-any-speed/?utm_source=techalert&utm_medium=email&utm_campaign=062713

Why Seaweed Biofuels Cannot Save the Planet

My general rule of thumb is that if you read headlines “X will save the planet” or that biofuels will do anything at all it’s better to just flip the page. However a report in the Guardian last week informs that seaweed biofuels can do all kinds of magnificent things, and as the headline above suggest saving the planet may be among them.

Can biofuels save the planet? No, and this can be demonstrated by some very simple, but powerful calculations.

The fundamental problem is simple: biofuels low power density. In every country each unit of land, on average, consumes X units of energy. On the other hand each unit of land can produce on average Y units of energy in the form of biofuels. The problem for biofuels is this: Y quite often is less than X.

Discussions about energy are marred by the myriad number of confusing units. Exactly why anyone would wish to use British Thermal Units is a perpetual mystery. Here I’ll use the more common and sensible unit of watts per square metre (W/m2) to describe power density. This has a lot of advantages, in particular that you can very quickly calculate land requirements for renewable energy installations. David MacKay has produced a remarkably simple and informative graph to demonstrate this point:

Quite clearly South Korea isn’t going to be getting 100% of its energy from onshore wind farms any time soon, but I’ll leave that to another post.

You’ll also notice that the United Kingdom uses energy at the rate of about 1.2 W/m2. This does not compare very favourably with 0.5 W/m2. provided by energy crops, i.e. biofuels. The exact power densities of existing biofuels can be debated somewhat, but quite obviously not to the point where you would not need country sized biofuel plantations to provide a significant percentage of UK energy supply. The difficulty is thatthis is true for all existing biofuels, including those derived from seaweed.

These simple facts however are clearly not known, or are ignored, by Damian Carrington who in his Guardian piece informs us:

Many see huge potential, with the UK government already including up to 4,700 sq km of seaweed farming cultivation in its future energy scenarios and another study finding it could in theory supply the world’s needs several times over.

Consider the first statement. What exactly is this huge potential? For some reason Carrington tells us how much land we could cultivate, but does not bother telling us how much energy we could get from it. However, it’s a rather straightforward calculation so let’s do it.

The UK government document he links to give us the information we need: yields of macro algae could reach 20 dry tonnes per hectare by 2025 and 1 million dry tonnes of micro algae give up 3.9 TWh of energy. This works out at 0.9 W/m2 .  Clearly, this power density is awful – just how much of the North Sea do people imagine is available for this stuff. And to put firmer numbers on this “huge” potential, consider what the UK government actually estimated we can get from 4,700 square kilometres worth of biofuels. A grand total of  5 TWh per year (Level 4 in the graph below represents 4735 km covered in algal biofuels by 2050).

https   <a href=www.gov.uk government uploads system uploads attachment_data file 47880 216 2050 pathways analysis report.pdf” />

Instead of “huge” potential for seaweed biofuels this is in fact completely marginal. According to the latest statistics from BP, total UK energy consumption in 2012 was 203.6 million tonnes of oil equivalent. This converts over to approximately 2,400 TWh. So, this supposedly huge potential for seaweed biofuels amounts to a mere 1% of UK energy supply. As always, beware the hype.

Now, the above discussion of the low power density of seaweed biofuels ought to convince anyone that they won’t be able “to supply the world’s needs several times over.” But to make it even clearer why seaweed biofuels can’t save planet, let’s consider scale. Right now, we produce just over 4 billion tonnes of oil per year. According to the Guardian’s story “a Californian firm produced genetically modified bacterium that can produce about 1kg of ethanol from 3kg of dried seaweed.” So, to totally replace global oil production with seaweed biofuels we would need to harvest 12 billion tonnes a year of dried seaweed (and remember the stuff we take out of the sea is not dry). To put such a figure in perspective remember all of the coal, oil and gas produced on the planet comes to 11 billion tonnes.

And how much seaweed do we harvest as of today? 17.3 million tonnes. Converting all of that over to seaweed biofuels would provide us with less than half a day of global oil demand.

You can now remove that “Seaweed will save the world!” bumper sticker.

http://peakoil.com/alternative-energy/why-seaweed-biofuels-cannot-save-the-planet

GM Explores Torque Converter DCT

Initial version of GM study incorporates a torque converter in the pressure chamber ahead of the dual clutches; benefits include improved launch and NVH

Initial version of GM study incorporates a torque converter in the pressure chamber ahead of the dual clutches;

benefits include improved launch and NVH

Though dual clutch transmissions have been very successful in sports- and performance-oriented passenger cars, the feedback from buyers of luxury cars and family vehicles has not always been so positive. Criticisms have centered on drivability and launch performance, particularly in North America, where drivers are accustomed to the extreme smoothness of planetary automatics and CVTs.

Intent on combining the DCT’s fuel efficiency with a conventional automatic’s ultra-smooth driving characteristics, GM engineers presented a paper at this year’s SAE Congress proposing a seven-speed DCT working behind a hydraulic torque converter in place of the conventional flywheel. As well as improving launch quality, the DCTC arrangement would also counter the other perceived drawbacks of DCT − its lack of sustained creep ability on grades, and its launch shudder and limited thermal capacity. The GM researchers also cited as a benefit the proposed transmission’s lower demands on its lubricant when compared to a conventional wet clutch DCT (wDCT): “Additionally, for wDCTs, high quality lubricating oil is required to achieve adequate friction and cooling characteristics which requires interval changes, leading to increased initial and routine maintenance costs.“

Operating Strategy

In terms of operating strategy, the torque converter (TC) is only used when launching from rest in first gear. After that, the lock-up clutch (TCC) remains engaged, although there is flexibility to allow slip of around 75 rpm to mitigate gear rattle and facilitate the use of low engine speeds for improved fuel efficiency.

The TC design investigated by the GM engineers is smaller than a conventional TC, but the housing containing the TC and the twin multiplate clutches is about 25 mm longer axially than on a standard DCT. In addition to the main benefit of eliminating the risk of launch shudder, as the shifting clutches do not slip, the authors cite other potential advantages of the arrangement. These include improved transient response and acceleration (thanks to the reduced inertia), the decoupling of the engine and transmission to allow engine idle without the aid of a clutch, and torque multiplication to improve engine starting under stop-start operation.

The latter will help ease some of the complex compromises surrounding dual mass flywheel design and NVH under restart, say the engineers, and DCTC users will perceive quicker vehicle acceleration response following an auto restart from rest.

On the all-important question of fuel economy, GM accepts that there will be extra energy losses in any torque converter. However, the paper shows that with the extra flexibility provided by the TC, the final drive ratio can be adjusted to derive maximum benefit from the TC’s ability to deal with NVH issues and to allow lower engine speeds through controlled slip. This is a useful advantage for the latest-generation downsized and downspeeded engines.

“Steady state operation at lowered transmission input speeds and high loads is made possible by controlled slip to attenuate rattle or provide NVH isolation which is not possible with dry clutches without loss of torque transfer or thermal concerns,” says the paper. “Drive quality is enhanced further in the engine downspeeded region by means of the torque converter facilitating improved torque transfer compared to dry or wet clutches alone. When a downshift is necessary while operating at low speed (around 1000 rpm transmission input), the TCC can be fully released, causing engine speed to flare, lower SR (speed ratio) to create torque multiplication, all the while engine torque capability is increasing. This leads to improved vehicle acceleration when requested, but also enables operating in a region that improves fuel economy.”

Conclusions

Overall, says GM, the most extreme of the final drive ratio options investigated allows the DCTC to actually improve (by 0.25 percent) on the fuel economy of a dry clutch DCT, with further potential improvements utilizing still-taller final drive ratios. Compared to a six-speed planetary automatic, the economy benefit is between 1 and 2 percent but, as the engineers explain in their summary, more is possible:

“The improved drive quality possible with the DCTC’s torque converter can enable aggressive shift and TCC pattern constraints that were shown to provide a 0.25 percent increase in fuel economy. A further increase in efficiency for a DCT utilizing a torque converter would be to relocate the shifting clutches of the DCTC concept to inside the transmission structure. The DCTC concept or use of a torque converter with shifting clutches internal to the transmission structure has the potential to be an enabler for DCT technology to achieve improved fuel economy and drive quality.”

http://drivelinenews.com/transmission-insight/gm-explores-torque-converter-dct/?utm_source=newsletter&utm_medium=email&utm_campaign=June2013

폭스바겐, 뉴 골프 TDI 블루모션 공개


폭스바겐, 뉴 골프 TDI 블루모션 공개

폭스바겐이 뉴 골프 TDI 블루모션을 공개했다. 작년 파리 모터쇼에서 공개된 컨셉트의 양산 버전이다. 3세대 골프 TDI 블루모션의 공인 연비는 31.23km/L에 달하며 CO2 배출량은 85g/km에 불과하다. 공인 연비는 구형대비 15%가 좋아진 것이다.

폭스바겐은 연비를 높이기 위해 많은 부분을 손보았다. 공기저항계수는 0.27로 낮췄으며 차고도 15mm 내렸다. 여기에 새로 디자인된 루프 스포일러를 추가했고 그릴을 막아 공기 저항을 낮췄다. 차고는 구형 대비 49kg이 감소했으며 스톱 스타트도 기본이다. 변속기는 6단 수동이 기본이다. 0→100km/h 가속 시간은 10.5초, 4단으로 80→120km/h 추월 가속 시간은 9초이다.

엔진은 1.6리터 배기량의 4기통 디젤 터보(EA 288)이 올라간다. 109마력의 최고 출력은 3,200~4,000 rpm 사이, 25.5kg.m의 최대 토크는 1,500~3,000 rpm 사이에서 발휘된다. EA 288은 내부 저항을 줄인 게 특징이며 연비를 높이기 위해 투 스테이지 오일 펌프, 저저항 베어링 등의 아이템을 더했다.

http://www.global-autonews.com/board/view.php3?table=bd_009&gubun=1&idx=10108

에너지 효율 지금부터, 내일은 늦어


이 시대 자동차업계의 화두는 에너지와 커넥티비티, 그리고 드라이버레스카다. 이 세 가지는 서로 밀접하게 관련되어 있다. 자동차의 페러다임이 바뀌어 가는 시대에 자동차업계는 공통 분모를 찾아 미래에 대비하려는 준비에 사력을 다하고 있다. 보는 시각에 따라 조금씩 차이가 있지만 앞으로 나아가려고 하는 입장에서 보는 자동차는 분명 ‘계속해서 탈 수 있을까?’가 최대의 고민이다. 지속가능한 이동성(Sustainable Mobility)이라고 표현한다.

그를 위해서는 에너지에 대한 답이 가장 먼제 해결되어야 한다. 더불어 연간 120~130만명의 교통사고 사망자를 줄이는 것도 반드시 풀어야 할 숙제다. 동시에 자동차에 대한 흥미를 유발해 소비를 살려 내야 한다는 절체절명의 과제를 안고 있다. 각 완성차회사와 부품회사들은 경쟁보다는 협력을 통해 이런 문제를 해결해야한다는데 동의하고 있다.

자동차회사와 부품회사의 경영진들은 기회가 있을 때마다 미래에 대한 그들의 생각을 밝히고 미래에 대한 대안 제시에 힘을 쏟는다. 아래 내용은 세계 최대 부품회사 독일 보쉬 그룹 회장 폴크마 덴너(Dr. Volkmar Denner, Chairman, Board of Management, Robert Bosch GmbH)가 말하는 에너지와 자동차의 미래에 대한 생각이다. 그 내용을 전제한다. (편집자 주)

정리/ 채영석 (글로벌오토뉴스국장)

전 세계적으로 에너지 수요에 대한 해법을 찾는 것은 현재 인류가 직면한 최대 현안 중 하나이다. 지금까지는 재생에너지 확대와 미래형 발전에 대한 논의가 그 대부분이었다. 하지만 좀 더 시야를 넓혀 보자.

에너지 효율성 개선과 전력 생산 방식의 재설계는 반드시 고려해야 할 사안이다. 국제에너지기구(International Energy Agency: IEA)는 전 세계 전기 공급에서 재생에너지가 차지하는 비율이 2035년 30%에 달할 것으로 전망한다. 나머지 70%는 기존의 에너지원을 사용해야 할 것이다. 하지만 이 자원들은 유한하며 향후 비용은 높아질 것이므로 이 자원들을 사용하는 것은 결국 기후 변화에 영향을 줄 것이다.

따라서 에너지 효율성 개선에 적극 나서는 일만이 우리가 에너지 소비 감축, 공급 안정, 재생에너지 이용 비용 감축,CO2 배출 감소, 그리고 에너지 고비용에 의한 충격 완화를 위한 유일한 해법인 셈이다. 특히, 재생에너지에 의한 에너지 공급이 증가하고 있는 현실을 고려할 때 에너지 효율은 주요한 역할을 할 것이다.

에너지 효율은 보쉬의 미래를 이끌어갈 주요한 성공 요인 중 하나가 될 것으로 기대된다. 보쉬는 전 사업부문에 걸쳐 이전보다 더 높은 에너지 효율을 제공하는 기술과 서비스 제공에 전력을 다하고 있다. 이러한 노력의 일환으로 에너지 및 빌딩 기술 사업 부문을 신설하여 시너지 효과를 극대화하고 새로운 사업 기회를 창출하고 있다. 보쉬의 환경 보호 및 자원 절약과 관련된 기술, 제품의 매출 비율은 이미 총 매출의 40%를 넘어섰다.

하지만 전 세계적인 관점에서 진전 속도는 그리 빠르지 않다. 현재 우리는 지구온도의 상승을 억제하기 위한 2°C 타겟을 달성하기에 역부족이다. IEA는 에너지 효율 전략이 전 세계적으로 활발히 추진된다면 2°C 타겟의 50%는 달성할 수 있을 것으로 전망한다. IEA의 수치는 가능성을 시사하고 있지만 현실적으로 우리 사회는 그렇지 못하다.

선진기술은 에너지 효율을 위한 모든 전략의 초석이다. 성장의 한계점에서 소극적인 태도는 해결책이 될 수 없다. 즉, 에너지 소비에 있어 전 분야에 걸쳐 관련 기술을 개발 및 보급하는데 주력해야 한다. 이 점에서 보쉬는 선도적인 역할을 해 나갈 것이다.

선진 기술은 에너지 효율의 기본이다. 선진 기술은 에너지 효율의 전제 조건이며 경제적 기회이기도 하다. 그 예는 보쉬의 네 개 사업부문에서 살펴볼 수 있다.

1. 지속 가능한 이동수단(Sustainable mobility)

이동수단은 전 세계 에너지 수요의 28%를 차지하며 세계적으로 차량 대수는 증가 추세이다. 따라서 에너지 효율성 개선 및 CO2 배출 감소를 위해 광범위한 기술을 도입할 필요가 있다. 이 점에서 내연기관이 앞으로 가장 큰 역할을 할 것으로 기대된다. 현재의 기술만으로도 내연기관의 연료 소비와 CO2 배출을 크게 줄일 수 있기 때문이다.

내연기관의 이러한 잠재력에도 불구하고 미래는 이모빌리티(e-mobility)에 달려있다. 보쉬는 전기모터, 파워일렉트로닉스, 에너지회수 제동시스템 및 배터리 시스템 등을 통해 이모빌리티에 관여하고 있다. 쾌적한 주행과 안락함, 그리고 현실적인 가격은 이모빌리티의 성패에 결정적 요인이다. 이 같은 요인으로 이바이크(ebike)는 단기간에 성공을 거두었다.

하지만 완전한 전기자동차를 위해서는 갈 길이 멀다. 그러므로 혁신적인 하이브리드 엔진이 반드시 필요하다. 특히, 플러그인 하이브리드는 순수 전기 구동을 통한 도심 운행은 물론 장거리 주행도 가능하다. 유압 하이브리드 파워트레인의 경우에는 이동식 기계, 버스, 그리고 쓰레기 수거 차량의 연료 소비 및 CO2 배출을 개선하였다. 또한, 배터리가 필요 없고 내구성이 강하며 상대적으로 저렴한 유압 어큐뮬레이터의 장점을 승용차에도 적극 활용하여 도심 교통에서 최대 45%의 연료 절감을 달성할 것으로 기대한다.

2. 효율적인 생산 기술(Efficient production technology)

일상에서 사용되는 제품과 마찬가지로 승용차 및 상용차 또한 생산 과정을 거친다. 그 결과, 산업 부문이 전 세계 에너지 소비의 32%를 차지하고 있다. 그렇다면 생산 공정에서 에너지 소비를 줄일 방법을 찾아보자. 예를 들어, 폴딩 프레스(folding presses)는 냉장고 및 식기세척기와 같은 가전제품 생산 과정에서 사용된다. 보쉬의 구동 및 제어 기술 사업부(Drive & Control Technology Division)는 “Rexroth for Energy Efficiency(4EE)”라는 프로그램을 개발하였다.

이 프로그램은 통합 에너지 시스템 설계, 효율적 부품, 에너지 회수 및 저장, 수요 중심의 에너지를 통해 최적화된 산업 시스템을 구현한다. 이러한 프로그램으로 재설계된 폴딩 프레스의 에너지 소비는 44% 감소한다. 이와 같은 맥락의 한 예로 주택을 건설하는 공정에서는 철골의 생산 단계부터 마지막 페인트 도색 단계에 이르기까지 이 같은 접근법을 사용할 필요가 있다.

3. 효율적인 빌딩 기술 및 새로운 빌딩 디자인(Efficient building technology and new building designs)

빌딩은 오늘날 전 세계 에너지 수요의 40%를 차지하고 있다. 따라서 신축 빌딩들에 대해 혁신적인 설계를 적용해야 할 뿐만 아니라 기존 빌딩들의 에너지 효율 개선 또한 필요하다.

현대적인 난방 기술, 온수 보일러, 그리고 제어 시스템을 통해 이미 많은 에너지가 절약되고 있다. 특히 상업용 빌딩의 경우, 전반적인 관리 서비스를 공급하는 외주 서비스 공급 업체와 함께 한다면 에너지 소비 절감에 많은 가능성이 존재한다. 특히 보쉬는 상업용 빌딩을 위한 통합적인 개념에 전문성을 갖춘 에너지 및 빌딩 기술 사업 부문을 신설함으로써 그 동안 보쉬의 빌딩을 통합관리하며 얻은 경험을 발전시켜 비즈니스 기회로 만들어 나갈 것이다.

4. 연구개발(Research and development)
이러한 모든 솔루션들은 보쉬 연구개발의 결과이다. 전 세계 80여 개 사업장에 4만 명이 넘는 연구 인력을 보유한 보쉬는 환경 보호와 자원 절약을 위한 기술에 전체 연구개발 예산의 45%를 넘게 투자하고 있다. 2012년 보쉬의 연구개발 예산은 총 매출의 8%가 넘는 약 45억 유로에 달한다. 같은 해 보쉬가 전 세계적으로 출원한 특허만 해도 4,700개가 넘는다. 보쉬는 이처럼 혁신에 집중하고 있으며 이러한 혁신에 대한 의지는 보쉬의 중심에 자리 잡고 있다. 보쉬는 기술이야말로 미래를 이끌어 가는 강력한 추진체라고 믿고 있다. 하지만 보쉬의 이러한 믿음은 기술에 대한 올바른 사회적 인식과 제도적 장치 마련을 전제 조건으로 한다.

우리의 행동 및 태도 또한 중요하다. 즉, 에너지 효율에 대한 사회적 인식이 개선되어야 한다. 그렇지 않고는 선진 기술의 대중화는 요원할 것이다. 또한, 산업 및 정치계도 이에 앞장서야 한다.

에너지 효율 제고를 위한 방법과 수단에 대한 논의는 정치, 산업 및 사회 전 분야에 걸쳐 더욱 활발히 이루어져야 한다. IEA는 에너지에 대한 세계 주요 지표를 심층 연구하고 종합 분석한 자료를 정기적으로 발표함으로써 그 역할을 다할 것이다. IEA 보고서는 에너지 효율에 대해 세계적으로 많은 관심을 받고 있다. 2012 세계 에너지 전망(World Energy Outlook 2012)이 그 대표적인 예이다. 동 보고서에서 최초로 제시한 에너지 효율 시나리오는 에너지와 관련된 논의에서 에너지 효율을 주요 주제로 부각시켰다.

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