Are electricity/hybrid and hydrogen powered cars any use

Ever since Toyota managed, with the Prius 2, to finally succeed in selling an alternatively powered vehicle in sufficient numbers for it to start to be taken seriously, the automobile industry has slowly been warming up to the idea of working on alternatives to diesel and gasoline/petrol, and people in general have started to also warm up to the idea of one day moving from internal combustion cars to alternative motorizations.

The main contenders for the moment seem to be 5, or rather 4 with one of them having two approaches.

1 - pure hybrid cars (like the Prius, or the hybrid Civic), and light hybrids like Mercedes and BMW among others are developing.
1.1 - the pure hybrids have a normal engines as well as a full electrical engine, so they can run on either, and then they have a number of systems to absorb the energy from breaking, slowing down, etc to load up the battery "for free". The idea is to run on electrical in the city, so you do not waste energy while stopped at lights, for example, (because an electrical engine does not stay running while the car is stopped) but then still have a normal fuel engine for long distances, so you avoid the problem of lack of range of batteries. In the end, clever systems allow the electrical engine to give extra whoompf to the fuel engine when needed, without putting pressure on consumption
1.2 - Light hybrids, on the other hand are basically normal cars which usually come equipped with two things. A small electrical engine attached to the gearbox or transmission, to feed extra power into the fuel engine when required while keeping consumption at its most efficient, much in the same way as the normal hybrids do; and a stop-go system which stops the main engine (which is a normal fuel engine) when the car is stopped, but allows it to immediately start again when you press the accelerator. By using these two systems and copying the energy efficiency system of full hybrids, manufacturers hope to provide full hybrid performances with a less complicated and cheaper system.

2 - fully electrical cars, like the Tesla, or the Volt concept car, and a number of models and concept cars currently being developed. These run only on an electrical engine, which therefore is at the same time much more efficient and responsive than a fuel engine. Besides not wasting energy running when not required, these vehicles also recycle energy from braking, slopes, slowing down and anything else is available to recharge the batteries, while accelerating faster and more smoothly than current cars.
One of the downsides is that batteries limit the range of these vehicles. To increase range they have to have more batteries, but this means they have to make the car bigger and heavier, demanding more energy to move the car, leading to less range. So, there is a limitation on how much more range manufacturers can pack into a car using current technology.
The Tesla avoids the lack of range by using light batteries similar to the ones in laptops and mobile phones, but this makes the car very expensive.
Most other cars stick to more traditional batteries to avoid the extra cost, but even so, electrical cars can be quite expensive.

So range has to be balanced out in relation to the cost of the whole system, and at the moment it is still difficult to achieve an attractive balance.

3 - Hydrogen fuel cells. A lot of manufacturers have been working on these, on and off, and governments have often cited the hydrogen economy as the solution to all our energy problems. Hydrogen fuel cells have probably gotten the most investment of all alternatives, because hydrogen is common in nature, namely in water, and it seemed like an infinite power source.

The idea is you feed hydrogen into the system, the system gets oxygen from the environment, applies a process called cataysis, and you get electricity on the one side, and water coming out of the exhaust.
There are other possible fuels that can be used instead of hydrogen, but the basic idea is more or less the same.
Despite all of the support, however, technical and safety issues have kept fuel cells from coming into the market, and I wouldn't be surprised if the development programs were put on the backburner to allow manufacturers to concentrate on hybrids and electrical cars, or simply on surviving the financial crisis.

4 - The aircar. The aircar is something that has been around for over a decade but has never really took off. It works, but it also has range problems, among others, akin to the probems of the electrical car.
The idea is simply that you put a tank of highly compressed air into the car, and use the pressurised air to run an engine. The engine is more complicated than that, but in essence this is what the concept boils down to. When the pressure in the tank gets lower, well, you just either plug it into a compressor and refill it, or you plug the car to a power plug and the actual car engine works in reverse to fill the tank.
There are currently a handfull of companies working on and selling this type of system, and Tata of India has signed an agreement with one of them to use the technology in India, so we'll see what that brings about, but for the moment the aircar is still pretty much an outsider.


Now, the main options are listed the big question is:
Are these cars cleaner?

and there are two answers to this: It depends. And, to a degree.
It depends on where you get the energy and this choice will define to what degree they are cleaner. They are also cleaner in terms of smog generating particles, but not really effective as a means against global warming.

The big problem with all of these "responses to global warming", is that they assume that energy comes out of nowhere. All of these systems have to be "fed", and this uses energy.
What I mean is, an electrical engine might emit nothing while running, but it still needs electricity. And eectricity has to be produced somehow. Therefore, your electrical engine will have zero emissions when running, but not if count the emissions of generating electricity to run it.
Only if your electricity production is emissions free will your car truly have zero emissions.
If you power up your electrical engine with electricity from a coal plant, you will still be generating loads of emissions in the process, only they will be only indirectly coming from your car.
On the other hand, if you happen to have a green energy supply, you will be completely clean.
Therefore, a Hybrid or an electrical car will only be as clean as the electricity you give it.

And the same goes for Hydrogen and pressurized air.
Hydrogen is really not a fuel. It is what they call an energy carrier. When you use energy to separate the Hydrogen from the Oxygen in water, you can get most of that energy back afterwards by putting them back together and making water again. It's as simple as that. If you feed it energy, then you can get it back later. But you do need to use energy to get the Hydrogen in the first place. So, where do you get that energy? If you get it from burning fossile fuels, you don't really get much of a benefit out of it.
So basically it's the same as the electrical car, only you get more steps in between, which will actually probably mean there are more inefficiencies.

Pressurized air is more or less the same. You need energy to create that pressure in the tank. You will never get more than that energy back, and in fact, you will probably get less. So, again, it depends on where you get the electricity from in the first place.

Comparison with current cars

According to coal power industry sources themselves, some older models of coal-powered plants will only use up about 30% of the energy existing in coal. Newer designs are able to provide top efficiencies of 40%-45%, and are getting close to 50%. Improvements are hoped to be able to reach as far as the high 60%s, achieving levels close to 70%, which is more or less where gas power is at the moment.
Naturally, there will be some loss of power until it gets to you, through dissipation, conversion losses, etc etc, but let us say that the efficiency of the electricity you get at home, which will come from a mixture of old and new plants, if it is coal sourced is somewhere between 35%-40%.
This will be the energetic efficiency of your electrically run car. Hydrogen and pressurised air will probably be a couple percent lower.

To compare, I can tell you that if you run a late generation diesel engine with electronic injection, peak efficiencies run around 40%-45%. Of course, average efficiencies will be lower. On an average day, your diesel engine will be making use of about 37% of the energy within the fuel.
A petrol/gasoline engine will be less efficient, using up only 25%-30% of the energy in its fuel.
On the other hand it will be lighter, compensanting for a small part of the lower efficiency, but it will never even come close to a diesel.

As you can see, if we take into account the source of the energy used to power alternative engines, a big part of the benefits disappear, unless, of course, you use green energy.

Conclusions

In a nutshell, alternatively powered cars will help fight global warming if they are powered using electricity, pressurised air, hydrogen, or any other 'fuel' generated using renewable energy.
If they are powered from the grid, using traditional sources of electricity, then most of the global warming benefits ebb away, and these cars are not much cleaner than a good Diesel car. Especially nowadays when we see smaller and smaller diesel engines, allowing smaller cars and higher efficiencies.
This fact allows for the cleaner cars in the market right now, and here I'm just speaking of end-of-the-exhaust emissions, not even including the emissions for the electricity used, not even being those popular hybrid cars, but rather small internal combustion cars with small but more efficient engines, like the Smart fortwo and the Toyota iQ.

The alternative types of engines are indeed cleaner in the sense that they pump out less particles into the air of our cities, so they leave the air cleaner there.
But they are not going to help much against global warming unless renewables make up a larger proportion of our primary electricity production.

In the end, we still have no free lunchs, and the only real way to decrease emissions from transportation is to simply be more organised and more modest in the way we travel:
- use public transport and bikes if that is an option
- travel less Kilometres or miles,
- travel less often,
- travel in smaller vehicles,
- share vehicles by travelling in the company of more people.

Fighting counterinformation - the supposed water vapour effect

Sometimes you just come across the weirdest and most pathetic arguments to support the idea that global warming does not exist, or that it is no big deal, or that it is not necessary to do anything about it, or that it is not human caused. In fact, the internet is bursting with such claims, very often coming from the same people, who apparently do not mind contradicting themselves with their own arguments.

Surprisingly, or perhaps not, many people buy into some of these arguments and in fact spread them as the gospel truth among friends and acquaintances.

So, I've decided to add another aim to this blog, namely, to counter some of the counterinformation that crowds the internet, and in the process, hopefully, give some simple arguments that people can use to convince others that this or other anti-environmental myth being spread around is wrong, or even a purposeful lie.

I'm starting by talking about water vapour, or steam.

Some campaigners argue that global warming cannot be caused by humans because the main responsible for the greenhouse effect is, by far, water vapour, and that since only 1% of vapour is human generated, then global warming is not caused by Humans.


Okay, there are a couple of true things there, as is usually the case. It is a common trick to suggest a starting point to an argument which is correct, to make credible a certain conclusion, which is reached by shadier reasoning. After all, the best lies are the ones with a basis of truth.
It is true that water vapour is responsible for most of the greenhouse effect and it is true that almost all of the water vapour comes from natural sources, for example evaporation of water from sea, lakes, and rivers, breathing by animals and plants, etc.

ALL the rest is a lie.

First mistake

To start with, the greenhouse effect is one thing. Climate change or global warming is another.

The greenhouse effect is, simply put, the atmosphere retaining the sun's energy in the form of heat, allowing us a comfortable temperature as opposed to the -200 degrees of space.
Water vapour is responsible for most, but not all of this effect.

Global warming, on the other hand, is an increase of the greenhouse effect, i.e., the atmosphere stores more of the sun's energy than before.
What this means is that, whereas water vapour is responsible for most of the greenhouse effect, it is not the main driver for its increase, i.e., it is not the main driver of global warming.

Therefore, whether Humans generate a small or a large proportion of the globe's water vapour is really not that relevant for the problem

Second mistake

We have no control over the emissions of water vapour (remember we only generate about 1% of it). Fortunately for us, even that extra 1% of vapour has little scope to increase the greenhouse effect significantly because water vapour does not stay in the atmosphere for very long. It condensates into water fairly rapidly, which means that its global warming effect is very limited in time.

But that is completely different for the other greenhouse gases, like CO2, methane, nitrous oxide and others which can warm up the atmosphere for decades or even centuries, and which are to a great extent the result of human activities.
The fact that the concentration of these gases has multiplied throughout our industrialisation, has led to an increase of the warming effect by these gases. Even if vapour stays the same, the global result will still be an increase of temperatures

Let's put this into a numerical example to make it clearer.
Imagine CO2, methane, and nitrous oxide are responsible for 10% of the greenhouse effect (not the real proportion but easier to work with). So, if the greenhouse effect makes our current temperature 200 degrees higher than the absolute zero temperature that exists in open space, then, 20 of these degrees will be due to these three gases.
Let's say that the concentration of these gases in the atmosphere doubles and we ignore all of the side effects, we might assume that our temperature will go up 20 degrees. Instead of summers with 25° C we might have to deal with 45°.

Even if these three gases are only responsible for 5% of the greenhouse effect, they will increase the temperature 10°.

And importantly, they will be responsible for 100% of the increase. Which means, we are responsible for it since we are the ones pumping more of the stuff into the atmosphere.
And because they stay in the atmosphere for very long, the effect will last decades or centuries, even without taking in feedbacks and tipping points which might be triggered.

So, it is really pointless to say water vapour is the main greenhouse gas so there's nothing we can do. It is the extra drop that makes the glass flow over. It doesn't matter it this drop happens to be water, wine, whisky, beer or milk. It will still flow over.

Mistake Three

Humans might only be responsible for 1% of the water vapour emissions, but this is not the whole story. This refers to water vapour directly generated by humans.
It 'forgets' that the higher the temperatures, the faster water evaporates. The more greenhouse gases we put out there, and the warmer they make the atmosphere, the more water vapour will be created, feeding back into the system with a vengeance.
In fact, recent studies by NASA indicate that the increased evaporation might go as far as to double the global warming effect in comparison to the warming that the other gases would generate on their own.

What about the Albedo effect?

This is a related issue to the third mistake. Albedo is the reflection of sunlight back into space. The higher the albedo, the less energy stays in the atmosphere warming it up. Areas covered with lighter colours, such as in places covered in ice, salt or light coloured sand, reflect a higher proportion of the sun's light than other areas (which is an important consideration now the north pole ice cap is going).

Clouds, which should increase in number if there is more water vapour in the atmosphere, have the same effect, reflecting sunlight and helping to keep Earth cooler. On the other hand, they also reflect energy back to Earth, avoiding it escaping back into space.

The overall result is still unclear, being one of the many difficulties in creating accurate environmental models. Some people have in fact suggested creating steam clouds to work as a sunshade as a way of fighting global warming.

Unfortunately, however, so far studies have indicated that more clouds tend to trap slightly more energy than the one they reflect back to space, so I'm afraid we should not really count on clouds to save us.