Saturday, May 05, 2007

Transportation Energy Independence

We, as a country, need to get away from using Middle Eastern oil for our transportation needs. Why, you may ask? The short answer is that the Middle East is not the place we need to look for in guaranteeing the economic security of this country. And transportation is essential to economic growth and stability.

Part of the longer answer can be found in part of an earlier post, Energy Independence:

The oil producing region of the Middle East is under an uneasy peace at best. Suicide bombers and the conflict in Iraq are the most visible and most reported violent incidents from the area. The Palestinians have elected a known terrorist group, Hamas, as their leaders. The kingdom of Saudi Arabia is among those listed in Parade Magazine as being some of the most ruthless dictatorships known with multitudes of human right violations. Of course, there is Iran making noises about wanting to join the nuclear club even though the president of Iran is clearly advocating using any and all means to wage war on Israel to wipe it off the map. Lastly, Islamic terrorists such as al–Qaeda are constantly stirring up trouble for everyone in the region.

Whether we like it or not, the United States has a vested interest in the Middle East for national security reasons. Again, according to the May 2001 Report of the National Energy Policy Development Group, the United States relies on foreign oil for 52% of its needs. Should the flow of oil be interrupted, then the United States would have a severe impact dealt to its economy as all sectors (transportation, manufacturing, & energy generation) would be affected. Those groups that have accused the United States government with trading blood for oil are partially right as the Government has the duty to protect the economic welfare of the country. However, these same groups do not take the time to understand the reasons for the foreign policy sometimes enacted in the Middle East. For example: The first Gulf War was waged for a singular purpose, and that was to secure valuable oil resources in both Kuwait and Saudi Arabia from Saddam Hussein's control. If those resources were under the control of Hussein, then he would have been able to economically cripple the United States and the rest of the world. Those groups decried the loss of life in this conflict. One wonders what they would do or say if Hussein had control of the oil fields and turned off the oil, thus depriving them of the ability to drive to the supermarket only to find empty shelves since the food couldn't be delivered…

So what are some of the options for reducing or eliminating foreign oil for our personal transportation needs? Let’s explore a few:

Electric-Drive Technology

The battery-powered car has been around since the turn of the century. The latest commercial incarnation of this technology was GM’s EV1, which could only be leased. After only a few years, these vehicles were pulled from the market.

The main problem with pure electric-drive vehicles is their range. While the EV1 was advertised to have a range of between 60 to 80 miles on a single charge, those claims were tempered with a recommended upper limit speed to achieve that range. Often, the range was less because those speeds were not realistic when competing on a highway with other vehicles powered by an internal combustion engine.

The limitation of range and speed of these vehicles is due to the limitations of the battery technology. The batteries can only hold a limited charge, and the batteries take up space in the vehicle. Weight also becomes a consideration, so the practicality of the vehicle now becomes a compromise between range, weight, speed, and size of the vehicle. Battery technology is improving, and may one day store vast amounts of electricity in a small space, but that day is not here yet.

An alternate energy storage solution that has been proposed (and is currently be researched) is a super capacitor. A capacitor in its simplest form is a non-chemical means of storing an electrical charge (batteries use chemical reactions to generate electricity). This is a new technology, so developing a device that can be mass-produced in quantity and price is some time away.

What is not often expressed about using an electric-powered vehicle is how to charge it back up for the next use. The most often method is to plug it in to a power outlet in your garage. The problem is that the recharging of several thousand of these cars will put a burden on the power grid. Considering that during the summer in California, there are rolling blackouts due to increased usage of electricity does not bode well for charging a bunch of electric vehicles, even if it is at night. The answer to this problem is to build more power plants, but where and fueled with what? Coal pollutes worse than natural gas, and both emit the greenhouse gases that the environmentalist / Global Warming crowds oppose. Nuclear energy is a no-no with the anti-nuke crowd, and there are only so many rivers that can be dammed to furnish power (providing the site passes the environmental review and doesn’t endanger any fish).

Electric-drive vehicles have their use in limited quantities, but these vehicles will not be a wide-spread long-term solution.

Hybrid Technology

Hybrid technology has been touted as the next best step to an environmental friendly and foreign oil dependence solution. And in some respects, that is a correct assessment.

Hybrid vehicles combine an electric-drive vehicle and an internal combustion engine (gasoline or diesel) in an attempt to optimize performance while reducing fuel consumption. When the battery pack of the vehicle reaches a low charge level or the vehicle needs an added power boost (such as passing another vehicle), the engine starts up automatically, powering a generator, and thus supplying the additional power needed by the vehicle.

A variation of this technology is known as plug-in. Like the electric-drive technology that was examined above, the vehicle is plugged in a standard wall socket to initially charge the battery pack. The initial charge is only good for 20-30 miles of driving, after which the engine in the car would then generate the power needed to keep the battery charged. This method might help keep the power grid from overloading, but that remains to be seen.

As discussed in a previous post, there are some concerns that hybrids are not as environmentally friendly as they have been portrayed. The chemicals and minerals used in the current crop of batteries are obtained at a greater energy and environmental cost than what could be acceptable. Of course, this same problem affects the all-electric vehicle that was discussed above. However, advances in battery technology may help reduce these concerns and environmental impacts. But remember – the fuel to run the engine to power the vehicle on the road and charge the vehicle in the garage has to come from somewhere.

Bio-Fuels

Bio-fuels have been getting a lot of press recently as being the answer for the near and middle term solution for energy needs. Bio-fuels include ethanol (with gasoline blends and as a stand alone fuel) and bio-diesel.

Ethanol is derived from the fermentation of sugar. The source of the sugar in the United States is primarily from corn, although other sources are used in other countries. The most successful example that I can think of is Brazil, where their entire transportation energy needs are met by domestic ethanol production from sugarcane – no oil is imported to the country for energy consumption.

Bio-diesel can be derived from a number of sources. Soybeans (United States) and jatropha nuts (India) are just a couple of crops that can be raised for the purpose of manufacturing bio-diesel. Bio-mass (organic recycling) is being used in Europe. Additionally, canola oil and recycled cooking oil have also been used as fuels in diesel engines.

Bio-fuels are extremely attractive for several reasons. The first is that current internal combustion engines can use them with little or no modifications. The second is that the technology to use these fuels is known and relatively mature. The third is that this source of energy is renewable. Last, in some instances, bio-fuel can burn cleaner than petroleum-based fuel. But…

…there’s always a downside. Growing crops to turn into fuel takes land that could be used to grow food crops. In countries that must choose between growing food and growing energy, this would be a difficult position. Environmentally, this could also prove to be a disaster in the making as countries would clear land (such as rainforests) to grow these crops and thus potentially wipe out endangered species. Already there are reports from Mexico and Holland about the rising food prices or unavailability of crops for food (or beer – horrors!!).

Additional concerns would also be that there is a report that using ethanol could be bad for the environment, and could cause additional health problems (link here). Also, the miles per gallon from using ethanol is approximately 15% less than using gasoline, and 11% for biodiesel. And using these fuels will still generate certain levels of CO2 which may not be acceptable even though they are supposedly “carbon neutral.”

Compressed Natural Gas and Liquefied Petroleum Gas

From an internal company webpage that cannot be linked to the outside:

An alternative fuel is natural gas. This chiefly consists of methane (CH4), and of all the fossil fuels, it has the lowest percentages of carbon that turns into to CO2 on combustion. Emissions of nitrogen oxides (NOx), soot and reactive hydrocarbons are also lower compared with liquid fossil fuels. One kilogram of natural gas, which is stored in pressurized tanks and therefore also called compressed natural gas (CNG), corresponds to the energy content of around 1.5 liters of gasoline. However, the low energy density compared with liquid fuels and the higher tank volume also cause disadvantages in terms of range and load area.

CNG is very attractive as a fuel that can be used to fuel internal combustion engines. I know for a fact that current engine technology can use CNG with little or no modification just by using a conventional carburetor and not fuel injectors. The main concern is the size and the weight of the tanks that would need to store CNG, and the safety of the tanks should there be an accident. Puncturing a tank could 1) be a fire hazard, and 2) have the potential to cause additional injury should the escaping gas propel an object.

An alternative to CNG is liquefied petroleum gas (LPG). Many of us use this gas to fire up our grills for that cookout, but it can be used as a fuel in the same way as CNG. But it also has the same concerns.

Hydrogen Technology

Hydrogen is the potential "king" of all fuels. It burns up completely in combination with oxygen, and pure water vapor is emitted as an "exhaust gas". Some examples of regenerative production possibilities are electrolysis using regenerative electrical energy from the sun, wind, water or geothermal energy. Regenerative hydrogen can also be extracted from biomass. To provide reliable supplies for hydrogen-powered vehicles, a standalone filling station network is required.

The main problem with hydrogen is storage. Hydrogen is the smallest of all molecules, and containing the gas reliably is incredibly difficult as it tends to seep through tanks and other storage containers. This could lead to a dangerous buildup in an enclosed space. The image of the Hindenberg is always on person's mind when someone mentions hydrogen.

And therein lies an inherent problem with hydrogen. It must be stored under high pressure to store enough gas for a vehicle burning hydrogen to get a decent range. But there is hope.

There is research that may lead to a reliable and stable method of storing hydrogen. The research centers on bonding hydrogen into a metal or nano-material matrix. This would stabilize the gas from leaking into the surrounding atmosphere. The gas could then be released in a controlled fashion as to be used in a power source for a vehicle.

Which leads us into the next topic...

Fuel-Cell Technology

One of the more intriguing power sources for vehicles are fuel cells. Essentially, fuel cells generate power through an electrochemical process, much like a battery. They convert chemical energy to electrical energy by combining hydrogen from fuel with oxygen from the air. Hydrogen fuel can be supplied in two ways - either directly as pure hydrogen gas or through a "fuel reformer" that converts hydrocarbon fuels such as methanol, natural gas, or gasoline into hydrogen-rich gas. The result of this combination is water vapor and electricity.

NASA has used fuel cells for years to power its spacecraft using compressed hydrogen and oxygen with great success. The main problem with this technology is that it is expensive, but cost should come down with time and development.

Tom's Vision for Fuel Independence

From an engineering standpoint, the internal combustion engine is fairly inefficient (30 percent efficiency at best) in providing energy for our personal transportation needs. Stop to think about it – every time a cylinder fires in your engine, you get the bang to convert the energy into mechanical motion, but a great deal of heat is also generated and goes out the tailpipe.

A better way is to directly convert the fuel into energy as efficiently as possible. In my mind, the fuel cell is just about the best direct fuel to energy conversion device thus far - fuel cells can achieve 40 to 70 percent efficiency, which is greater than the 30 percent efficiency of the most efficient internal combustion engines. Technical challenges toward developing fuel cells are many – safety, fuel supply & distribution, and cost are just a few of the problems that would need to be overcome. But this will not happen overnight – it will need to occur in stages. Until those challenges have practical solutions, then here’s the direction I think we need to go:

When I was in Germany, I drove a Mercedes C230 with a diesel engine. Outside of the initial startup rattle that sounded like a truck engine turning over, the engine was quiet and powerful. Getting the car up to cruising speed (250 kph = 155mph) on the autobahn was no problem, and the response of the vehicle was excellent. Using diesel engines in passenger cars as well as trucks & SUV's while supplementing the petroleum diesel fuel supply with bio-diesel would make an almost immediate impact on how much petroleum is imported to this country. This would be the first step, but would need time to implement as this industry would need to ramp up to meet the level of demand that is currently dominated by gasoline demands. Can it be done? Yes, but the stigma of diesel engine for passenger use in this country would need to be overcome.

The second step would be to pour the development money into the R&D for both battery and fuel cell technologies. The vehicle configuration that makes the most sense to me is a battery-powered vehicle that can be recharged by a plug in and by a fuel cell for those extended trips. Such vehicles are quiet, powerful, and as a side benefit, environmentally friendly. A hydrogen infrastructure would need to be developed as well as a beefing up of the electrical power grid for the extra demand, but this is all possible.

The third step? Mr. Fusion, but that’s way out in the future, but we will need to get back to that later…

Remember you read it here first!!

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