Observing Microsoft, Part 4

This day is an interesting one for Microsoft. First, Ballmer sends out a letter to employees that states that he will resign within 12 months. Then it is announced that there is a committee on the Microsoft board, containing Bill Gates, of course, which has the responsibility of finding a new CEO. No, I suspect that Ballmer is not on that committee.

Some writers are saying that Microsoft is not forcing Ballmer out. But think about it. If you had to get rid of a failed CEO who owned 333 million shares of your company's stock, what would you do? It was most certainly a negotiated force-out. With a legal release. And probably some kind of honorary employment that requires Ballmer to only sell within certain windows of time and keeps him on a leash.

Welcome to the mobile revolution.

I must say that this change is way too late. After all, in 2010 people were already clamoring to fire Ballmer. And doesn't clean things up soon enough. Obviously Microsoft's board or directors should have been doing this for the last several years!

The reorganization that Ballmer has been accomplishing seems like a smart idea, except that it is trying to make a silk purse out of a sow's ear. It's made for the PC era which is slowly fading away. Still, the new organization is probably one less thing that a new CEO will have to worry about. That is: if he accepts this vision for the new Microsoft. A vision that depends upon Microsoft succeeding in the mobile revolution. Still with the reorg, Microsoft has a corporate culture that can't simply turn on a dime.

And Windows is exactly the problem.

Energy Efficiency

The mobile revolution has created two very interesting trends in the computing landscape. These are battery longevity and cloud computing. In order for batteries to last a long time, the products they power must be energy-efficient in a system-wide way. In order for cloud computing, with its massive compute farms, to be cost-effective, each server must be singularly power-efficient and generate as little heat as possible since cooling is a power consumption concern as well.

Of course battery longevity also affects electric cars like the Tesla. But, when it comes to computing, the battery longevity comes from three sources: more efficient batteries, hardware systems where power efficiency is an integral part of their design, and finally the economical use of resources in software. In the cloud computing arena, instead of more efficient batteries we are concerned with heat dissipation and cooling strategies.

More efficient batteries is a great thing, when you can get them. But advances in supercapacitors and carbon nanotube electrodes on various substrates is yet to pan out. This means that hardware systems such as SoC's (Systems on a Chip) must be designed with power efficiency in mind. Power management solutions that allow parts of a chip to turn themselves off on demand are one way to help.

Even at the chip level, you can send signals between various components of an SoC (System on a Chip) by using power-efficient transmission. For example, the MIPI M-PHY layer even enables lower power consumption by the transmission of the high-frequency data that usually chews up so much power. Consider using a camera and processing the data on-chip. Or using a scaler that operates from/to on-chip memory. These applications involve images, which are huge resource hogs and must be specially considered, in order to save significant amounts of power.

But there's more to this philosophy of power management, and this gets to the very heart of why SoC-based gadgets are so useful in this regard. General tasks that use power by processing large amounts of data are handled increasingly by specialized areas of the SoC. Like image scaling and resampling. Like encrypting and decrypting files. Like processing images from the onboard cameras. Like display processing and animation processing. Like movie codec processing. Each of these applications of modern gadgets are resource hogs. So they must be optimized for power efficiency at the very start or else batteries simply won't last as long.

Of course, you could simply user a bigger battery. Which makes the product larger. And less elegant!

Windows?

So what is the problem with Windows? The Wintel architecture wasn't built from the ground up for power-efficiency. Or distributed specialized computing, like so many gadgets are constructed these days. And now you can see what a daunting process this must be for Microsoft engineers that basicaly have to start over to get the job done. It will take quite a bit of time to get Windows to run on an SoC. Almost all implementations of Windows today are built to run on discrete CPUs. The Surface Pro appears to use a regular CPU board with a stock Intel part.

You see, power efficiency isn't just a hardware problem to solve. The software must also have this in mind with everything it does. The consumption of resources is a serious issue with any operating system, and affects the user experience in a huge way. I can't even begin to go into the legacy issues with the Windows operating system. The only way is to rewrite it. One piece at a time.

This problem has led many companies who lead the cloud computing initiatives to use Linux for their server operating systems. Mostly because it can easily be tailored for power efficiency. The server operating system share of Unix-based operating systems is 64%, compared to about 36% for Windows.

Servers are almost certainly going to go the way of the SoC also, with dedicated processors doing the expensive things like video codec processing, web page computation, image processing, etc. But I do see multiple cores and multithreading still being useful in the server market.

But not if they increase the power requirements of the system.

On mobile devices, Windows hasn't done so well either. Windows Phone probably has less than 3% of the mobile space, if that.

The Surface never clicked

Why didn't the Surface RT and the Surface Pro tablets succeed? First off, it's possible that they are simply yet to succeed. I just had to say that.

But more likely they will never succeed. It's hard to move into a market where your competitors have been working on the hardware solutions for years. And when hardware isn't your expertise.

At first, the Surface marketing campaign was all flash and no substance. A video of dancers clicking their tablet covers into their Surface tablets was certainly criticized by a few bloggers as vacuous. The main problem was it stressed the expensive keyboard cover, and skirted the issue that the cover is totally needed. With the cover, the Surface tablet becomes just a crappy laptop. That you can't really use on your lap, because of the kickstand. Their follow-up video was curt and to the point, but sounds a bit like propaganda. saying "Surface is yours. Your way of working. Your way of playing".

Yeah. Trying to get into the mind of their prospective users.

But it's clear that their strategies were simply not working, because they went to the old adage "if we don't look good, then maybe we should just make them look bad". And they started releasing anti-iPad ads. The first one used Siri's voice to sum it up "do you still think I'm pretty?". They compared the price of the legendary iPad to the Surface RT without a cover. I suspect that a Surface RT without a keyboard cover is pretty much useless. The next anti-iPad ad compared features in a less quirky way. But anybody using a Surface RT knew that it didn't support the apps that the iPad has, or really have any of the advanced iOS/iTMS ecosystem in place. And without the keyboard cover it was cheaper, certainly. But you really had to have the cover to get full functionality.

So Microsoft decided to drop the price. This was echoed in the nearly $1-billion charge they took that quarter. Then they followed up by dropping the price of the Surface Pro! It seems desperate to sell their inventory. Otherwise they will be taking another huge charge against Windows revenues like before.

Curiosity

Someone once said that curiosity killed the cat. But that's really giving a bad reputation to a key form of behavior that has distinguished humankind ever since the invention of fire. And, it turns out, one of the main ingredients of creativity is curiosity.

You see, in order to put things together that normally might not go together and create something new and distinctive, one has to be curious about lots of things. Becoming a semi-expert in several fields is the domain of the generalist, the polymath, the renaissance person.

Let's consider an example: quantum physics always interested me because there is quite a similarity to group theory in the modeling of bosons and hadrons and their decomposition into quarks. Learning about one can help in understanding the other. And, well, number theory has a lot in common with group theory as well.

Companies

But companies can't really consist of a lot of polymaths. So a company does the next best thing and it puts together lots of people who are experts in their fields. And then it binds them to a task that keeps them concentrating on the company's goals. High-level executives should probably be polymaths, though, because they will have to know a little bit about all the technologies within their domain in order to do a good job. And they will have to put them together into the proper path for the company. They make the goals that the experts within the company relentlessly pursue. They see the value of research, albeit limited, within areas that might be immensely profitable in the long term.

What to be Curious About

Now let's discuss one of the ramifications of curiosity for business: top-down management can only work when the top person is curious and willing to consider lots of things. Though, this doesn't mean you have to boil the ocean to find the next greatest thing. But it does mean that you have to at least pursue the things you may find that bear on your goals, even when they seem to be unrelated. The trick is deciding which of them to prune away, and how quickly to do that.

What is there to be curious about these days? Well, this is the domain of the futurist. Which future technologies will bear on your business? If you are running an automotive business, then the mechanics and synergy of hybrid drives is one area to be curious about. And to have active research into. But if you are thinking even farther ahead, you should be very curious about all-electric vehicles and technologies that bear on them. This would include batteries, supercapacitors, fuel cells, new low-power processors and their use in distributed control techniques, the inclusion of camera technology and object-recongnition technology.

Redundancy vs. Simplicity

When you build a car or a gadget or even a company, the most important thing is that it should not break down and thus fail to achieve its intended use. This means you have to be curious about techniques for redundancy (because parts break down and so you can use multiple parts to support and back up each other to achieve a higher mean time between failures) and simplicity (because the fewer parts something has, the less there is to go wrong, and the more reliable it will be). And you should be curious about how these two contrasting principals trade off against each other. But this also means you have to fight a battle at two fronts: making things more reliable and making parts more simple by combining them.

Consumables

In the modern day, minimization of the use of consumables becomes a priority. In the ecological sense, this means using fewer things that can't be recycled. In the energy sense, this means having devices use less power to achieve their intended uses. Executives should be curious about these things because they are becoming increasingly important. For the auto executive, this comes from the increasing rarity of fossil fuels, and the implications for their rising costs. For the gadget executive, this comes from the trend towards mobile computing, and the subsequent use of batteries.

Energy becomes a consumable in both cases. But, within the discipline of batteries, we are learning more quickly in the gadget world than we are in the automotive world, I think. This has spawned techniques in distributed processing and custom chip design.

Modeling: Vision and Execution

It is important to be curious about the modeling of things. Let's consider a real-life model for a business and how that has led to immense success.

It was once said to me (I was a CEO at the time, and this was said by another CEO) that a company cannot be both a hardware company and a software company simultaneously: it was a recipe for failure. Well, Apple has proven this maxim to be utterly false. One side of Apple is curious about the vision of the coolest, easiest devices. The other side of Apple is curious about how best to manufacture them to meet inevitable user demand: it's all about vision and execution.

Apple's model of creating the coolest hardware along with the easiest-to-use software is a winning solution. This took decades of work, though, to prove it: Steve Jobs operated with conviction and so he has been proven right.

And this model appears to be right because it is true that the greatest profit can be extracted when you do this. Yet, and this is massively important, this model is not sustainable unless you perfect your ability to execute. And Steve knew this, which is undoubtedly why he hired Tim Cook. Tim has brought the science of supply chain management, manufacturing, and sales to a high art through his superlative logistics expertise. This is not something easily accomplished.

Not Being Curious

The downside of not being curious is that your products will be quickly obsoleted by those companies that have leaders that are curious. And apparently it doesn't matter how much money you have. If you are not curious enough to figure out the model, the technologies, and thus the mechanics of disruption, then you yourself become disrupted by an opponent with the ability to execute.

Vision counts. When you lack the innate curiosity to form a vision, you lose.

Disruptive Technology, Part 2

The times, they are a-changin', and maybe it's time to change the batteries as well. In the first installment of disruptive technology, we talked about brick-and-mortar disruption by internet commerce, the disruption of books by digital media, the constant revolution in data storage, and the disruption of several markets by smartphones and tablets.

Now we will talk about some another market currently undergoing disruption.

Internal Combustion Engines

Most people would think that the internal combustion engine is here to stay. This is almost certainly true because of the near-impossibility of replacing aircraft engines with anything else at present. But with cars, some leaps and bounds have occurred. And the market is beginning to see the effect of technology disruption.

Hybrids

Hybrids are here and are rapidly maturing as a market. The revolutionary vendor Toyota farmed out an entire market and became the Apple of hybrid vehicles with its Prius. Now most manufacturers have a hybrid car and this is increasing the average efficiency of petrochemical fuel usage. Which has been lowering the demand for three years now. But hybrids are still dependent upon gasoline. Is it possible to dispense with the petrochemical use and make a vehicle that only uses batteries?

Electric Cars

Electric cars do exist and are in common use already. The Chevy Volt, the Nissan Leaf, and the Tesla Roadster are examples of all-electric cars (except the Volt, which has a range-extending internal combustion engine, of course). Electric cars provide zero pollutants (and no tailpipe). The engines are quiet, and efficient, providing better acceleration than internal combustion engines. And they don't use foreign resources. So they can reduce the dependence upon an imported consumable.

But there are issues with electric cars: maximum distance traveled, charging, acceleration, batteries, the carbon footprint of making the electricity in the first place, and of course payoff.

Maximum Distance Traveled

The Tesla Roadster travels 244 miles between charges, but costs $104,000. The new Tesla Model S is coming out this summer with 160 miles between charges and has an extended-range model that can go 320 miles between charges. And the price, at about $40K to $60K comes down to less than half that of the Roadster. But it has about the same acceleration capabilities.

Other electric car offerings, such as the Chevy Volt (40 miles between charges, but with a range-extending internal combustion engine), and the Nissan Leaf (100 miles between charges) are extending the options for prospective customers.

But the scoop is that the Volt is really more like 33 miles between charges.

Charging

Charging one of these cars is actually quite cheap: somewhere between $2 and $4 per "tank". That's certainly encouraging, given that a tank of gas cost me $80 this morning. Yet it took me about 4 minutes to fill up.

But wait, how long does it take to charge these cars? On a 110-volt outlet it could take as long as 20 hours! With a 220V outlet, this goes down to 8 hours. You might be installing one of these in your garage. It's not really too foreign since your dryer has the same basic hookup.

But the huge amount of time it takes to charge is still reducing the usefulness of these devices. I have heard of quick-charge stations; couldn't we just use those?

Practically all of the "quick-charge" stations are in Southern California. So much for going to the gas station! Even a quick-charge to 80 percent capacity is an agonizing 30 minutes of time.

Yet, Nissan seems to have come up with a ten-minute charging solution by changing the material of the electrode in the battery. This could be just what is needed. Or at least it's a start. And it may not appear in use for quite a while, as is typical for battery advancements.

Acceleration

These cars will have to be as ballsy as mine before I buy one. Well, in some cases they actually are! The Volt goes from 0-60 MPH in about 8.5 seconds, 10 seconds with four occupants. The Nissan Leaf goes from 0 to slightly over 60 MPH in 11.9 seconds. Ho hum.

But the real surprise is the Tesla Roadster with 0-60 MPH in 3.7 seconds! And the Tesla Model S approximately matches this. So there are some more expensive options out there for those of us who like to drive fast and feel the torque.

The improvement in acceleration was achieved by replacing lead-acid batteries with lithium-ion batteries. Now, the amount of energy per pound matters almost as much as the total amount of energy stored.

Batteries

The main issue with electric car batteries is how much power they can store per weight. Lead-acid batteries (used in traditional internal combustion engine cars) can store 30-40 Watt-hours per kilogram. If we use a Nickel-metal hydride battery, we can get 30-80 Watt-hours per kilogram. If we step up to Lithium-Ion batteries, though, we can get 200 and more Watt-hours per kilogram, though typical Lithium-polymer batteries are at about 100-130 Watt-hours per kilogram.

But each of these technologies has a different issue: how many charges it can withstand before requiring a replacement. On the Tesla electric cars, a "blade" technology allows part of the batteries to be replaced in the shop on a need-be basis.

Some new Lithium-ion battery types can withstand 7000 or more charges, which means they could practically last more than ten years.

The idea of swapping out batteries for freshly charged batteries is a possible solution to the charging problem, and it can also alleviate the problem of the lifetime in terms of the number of charges. Then you could go to the gas station (actually a battery swapping station) and get an instant refueling. The time to refuel the batteries would then be spent in the charging stations themselves. Hmm.

So what we need is a standard battery type that is shared between all electric cars. Right now, the battery is really one of the major advantages that each electric car vendor actually has. With the right standard (that had the right flexibility), though, the research on batteries could go on in parallel to the electric car manufacturers and improve incrementally over time. It would create a new industry.

Carbon Footprint

These cars are electric, right? They are totally green with no emissions! Oh, wait... where does their fuel come from?

Really, the carbon footprint of an electric car is the footprint of the creation of the electricity used to charge the batteries again and again. So, where does your electricity come from?

In China, the explosion in electric and hybrid cars has led to an interesting problem. It turns out that the carbon footprint of making the electricity is much worse than that of using internal combustion engines in the first place. This is because they use coal to make 70 percent of their electricity (cough).

Payoff

These cars will certainly pay off over time, since we won't be buying gasoline, right? It turns out that electric cars are quite expensive compared to their internal combustion and hybrid cousins. Well, the payoff probably won't be there until oil gets to about $300 a barrel.

As for the Tesla Roaster: payoff isn't really the right word. It's about the satisfaction of driving one, I hear. Payoff is getting better for the Tesla Model S, though.

Their recently introduced (but yet to be manufactured) Model X is more of an SUV when compared with the Model S's sedan format.

Planes, Trains, Trucks

The larger hauling capacity of trains and the extreme energy requirements of aircraft are in another league from the hauling and energy requirements of personal transportation. Diesel fuel, Jet Fuel, and gasoline is used for these situations because the energy density of petrochemical fuels is about 35 times the energy density of the best batteries in use with electric vehicles today.

Currently only Hydrogen has the possibility to displace it, when compressed. But even Hydrogen uses up more space: it takes six times the volume to store an equivalent amount of Joules of energy using Hydrogen than when using gasoline.

So, perhaps the internal combustion engine is here to stay for a while. At least for the heavy lifters of industry and travel.

What Needs To Happen?

Can technology overcome the problems with electric cars? To some extent and within a limited usage constraint, it has already. But to get to the point where even aircraft can practically become electric, some changes are going to have to occur.

We need a serious advance in battery energy density. If you consider that the efficiency of the electric motor is about 75% compared with the 20% efficiency of the internal combustion engine, and if you consider the factor of 35 of energy density between the best batteries and gasoline, the energy density will have to go up by a factor of at least about 11 or 12 before we can see batteries powering Dreamliners. But is that all that's needed?

No.

The amount of time it takes to draw a given amount of energy from a battery must also go down, so you can increase the work temporarily for harder tasks. And the charging time will have to go down, even if battery swapping stations can become the standard.

This means that batteries and capacitors are going to have to merge. A capacitor can be charged in very little time, hold its charge for a very long time, and discharge almost instantly. If a battery can be switched into capacitor mode, this will go a long way to improving the usefulness of batteries for driving mechanical systems that require a large amount of work.

Energy, Part 1

As the world moves closer to fossil fuel depletion and global warming seems to be increasingly caused by carbon dioxide emissions, sources of green energy have become more and more important. But what are green energy technologies and how far have they gone towards adoption? What hold-ups are there in relinquishing fossil fuels? What can satisfy humanity's diverse and enormous requirements for energy? To even start to answer these questions, we need to know how energy is harvested, stored, and consumed.

Harvesting Energy

Since Einstein we have known that energy is contained in all matter, and his famous formula represents an upper limit on how much energy can be harvested. And in a few cases, we have determined how it can be extracted, with varying efficiencies. Let's look at a few. The first method of energy extraction is from an exothermic (heat-producing) chemical reaction. This method is used in internal combustion, and it releases heat, measured in Joules. For example, when combusted with oxygen the following fuels release this much energy in kiloJoules per gram:

• Acetylene 11.8
• Ethanol 27.3
• Coal 17-21 (sub-bituminous) 29-33 (bituminous or anthracite)
• Kerosene (Petroleum) 43.1-46.2
• Methane 50.6
• Gasoline 51.6
• Hydrogen 120

The reason Hydrogen has so much promise is due to its clean-combustion: water is the only by-product of combustion with oxygen. The other fuels release CO2 in varying amounts per kiloJoule of heat produced: gas is the least at 1.2 moles of CO2 per megaJoule and coal is the most at 2.0 moles per megaJoule.

The conversion of harvested heat into electricity or mechanical motion is quite a different matter.

Most people know that internal combustion engines are really controlled explosions. The addition of heat to a gas causes a significant change in its density. This change is implied by the law of ideal gases:

PV = nRT

Here, P is the pressure, V is the volume, n is the amount of the gas, R is a constant, and T is the temperature.

From this, we can see that when you increase the temperature, while keeping the amount of gas and the volume it is contained in constant, then you must increase the pressure proportionally. A massive increase in heat and a chemical reaction can create an explosion, which is a massive increase in volume. This is what happens in an internal combustion engine: the gas explodes, the massive increase in pressure drives a piston, and the motion of the pistons drives a cam shaft.

In modern cars, this is used to propel the car forwards, as work.

This can also be used to move a rotor and generate electricity through electromagnetic induction. Many power plants work this way, including the Moss Landing power plant in California.

Chemical reactions, to generate heat and drive turbines, generate about 65% of the world's electricity requirements today.

The second method of energy extraction is the harvesting of kinetic energy from matter that is already moving, such as water and air. This energy is almost always harvested using a turbine.

Have you seen the wind machines dotting the hillside near you? Those are wind turbines that harvest electricity from the wind itself, with very little effect on the environment. This is commonly called wind power, and is a renewable energy source, powered indirectly by the sun with the process of convection, and the turning of the earth, through the Coriolis force. Wind power currently generates about 1% of world electricity requirements, though the cumulative output is growing exponentially, suggesting in 20 years that an 8-fold increase will occur.

Another kind of kinetic energy that can be harvested is moving water. This is commonly called hydroelectric power. I'm sure you have noticed that water runs downhill. Here gravity itself is harvested because of the inexorable tendency of water to find a common level. Water, usually stored in a reservoir (fed by rain or snow melt) is stopped up at a dam. Some of the water is allowed to flow into a river, and in between the reservoir and the river is a turbine that runs a generator. About 1.5% of world electricity requirements are generated using hydroelectric power.

What happens when you mix exothermic reactions with turbines? The heat produced by chemical reactions is often used to heat water to produce steam. The state change that occurs when water is converted to steam means an increase in volume by a factor of approximately 1700 times. The increase in pressure means steam can be used to drive a turbine to generate energy, in a technology known as steam turbines. This process is used in aircraft carriers to great effect: it can drive a steam catapult to propel planes from its deck, or it can be used to drive the main screws to propel the carrier through the water. This process is also extremely well-suited to energy generation via electromagnetic induction. About 90% of all electrical power in the US is generated using steam turbines both in conventional coal, natural gas, fossil-fuel, and also through nuclear power plants.

A third method of energy extraction is via the photoelectric effect. This is the method that solar cells employ to harvest energy directly from sunlight. The efficiency of this technique is determined by how many photons are required to generate a single electron. Modern solar power plants, however, usually employ a different method to harvest energy. The technique is known as solar collection. In this technique, mirrors and lenses concentrate the sunlight from a large area to a small area. Once in a small area, the sunlight can be used to heat water in a closed steam system, as in solar towers. This steam is then used to drive a steam turbine, which drives a generator, which generates electricity. Usually the mirror is shaped like a parabolic trough, and instead of heating water directly, it heats molten salt and then the molten salt is used as a heat source for the power generation system.

Solar power is considered to be renewable since it harvests energy directly from the sun, the effectively continuous free energy source.

The largest solar power station in existence, in the Mojave desert of California, generates 354 MW of power. In comparison, the Three Gorges Dam hydroelectric power station located on China's Yangtze river, generates 18.5 GW of power, and, when finished, is intended to generate a total of 22.5 GW of power. As of yet, solar power hasn't yet reached a generating level of even 0.1% of the world's electricity requirements.

A fourth method of energy extraction comes from the energy contained in matter itself. Nuclear power currently works by exploiting the chain-reaction properties of U-235, an isotope of Uranium. In a nuclear power plant, the runaway chain reaction is usually moderated by water and other slow-neutron absorbing substances, like graphite. Nuclear reactors generate heat in abundance. This heat is used to heat a second, insulated water cycle and generate steam, which then drives a turbine and a generator to make electricity. But it is also possible to use molten sodium, an excellent neutron absorber, to transfer the heat of the nuclear reaction, in a so-called liquid metal reactor.

Uranium is about 40 times more commonly occurring naturally than silver, and so it is hard to prevent technologically advanced nations from acquiring it. For instance, in Israel, the sands of the Negev desert contain trace amounts of Uranium. The separation of U-238, the isotope of Uranium that makes up 99.3% of naturally-occurring Uranium, from U-235 (that makes up the rest) is complicated.

The Diablo Canyon nuclear power plant
Source: PG&E via Power Plants Around the World

Nuclear power presently generates considerably more energy than solar power. For instance, the Diablo canyon nuclear power plant in California generates 2.4 GW (7.5x the largest solar power plant) and makes up about 20% of the Northern California power grid.

Nuclear power accounts for 14% of the world's electricity requirements today.

However, nuclear power has some serious drawbacks. The disposal and storage of radioactive waste (particularly spent nuclear fuel rods) presents problems that, while they can be solved, are nonetheless controversial. The Östhammar facility in Sweden shows promise for treating this problem with the proper respect and care required for 100,000-year storage systems. The site was chosen partly because the rock at the waste-storage level is relatively free of fractures. After the rock is excavated, two tons of spent fuel is stored in 25-ton copper canisters. Each copper canister is then welded shut using a special robotic welder and robotically deposited in an individual tunnel in the repository. Then, bentonite clay is injected into the tunnel, mixed with water, to expand into place. This forms a watertight barrier that is essentially earthquake-proof. The storage repository is scheduled to open in 2025.

Portable Energy Storage

Once energy is harvested and converted to electricity, it may be stored for later use and carried around. You can consider fuel to be a portable energy storage system also, although usually fuel needs to be combusted and this makes it normally unsuitable for battery usage. But even this axiom is being challenged by the fuel cell.

Portable energy may be stored in several ways. The first is a battery, which generates electricity through electrochemistry. The second is a capacitor, which stores energy in its electric field. The third is a fuel cell, which, similar to a battery, uses an electrochemical reaction to generate electricity.

We grade portable energy storage systems on:

• capacity, which is the amount of electric charge they can store
• charge time, the amount of time required to return the device to full or substantial charge
• discharge rate, the maximum amount of constant current the device can produce
• energy density, a measure of how much energy the device will produce by weight

Each characteristic is useful for different uses. For instance, in an electric car, the energy required to start the engine and move the car from a standing start is related to the discharge rate. Also, a device must be light in relation to the amount of energy it contains, and thus energy density must be high for an electric car battery.

On Hydrogen Fuel Cells as an Energy Source

The energy density of hydrogen gas is the highest of all chemical sources, in excess of 120 kiloJoules per gram. The energy density of a lithium-ion battery, in contrast, is only about 0.7 kiloJoules per gram. Of course, nuclear material such as U-238 has an energy density of 20 gigaJoules per gram. Antimatter contains a theoretical maximum of 180 teraJoules per gram. Presently, nuclear material and antimatter are unsuitable for portable energy storage systems due to the weight of a nuclear reactor and the general unavailability of antimatter.

All above considerations point to hydrogen fuel cells as the most likely successor for portable energy systems. Per weight, hydrogen fuel cells are about three times the energy density of gasoline. The volume of hydrogen, even stored as a compressed gas, far outstrips that of gasoline for comparable amounts of energy generation. This makes hydrogen use a bulky problem.

Also, most all the world's hydrogen production emits CO2, since it uses the steam methane reforming process. So some improvement is needed to cut down on its carbon footprint.

Improving Batteries

The characteristics of a capacitor are short charge time and fast discharge rate, really the opposite of a typical battery. This is why several companies are trying to merge the two technologies to get the best of both.

Supercapacitors are a new technology which promises to replace the battery as we know it. One valuable attribute of supercapacitors is the apparent ability to charge and discharge thousands of times, making the device stable enough to outlive the device it is intended to power. The main problem with super- and ultra capacitors (battery-capacitor hybrids) is the energy density. The capacitance of these devices is directly proportional to the electrode surface area. The use of materials like activated charcoal (with its unbelievably large surface area) have increased the energy density into the usable domain. The promise of nanotechnology, such as nanotube carbon filaments, also can lead to high surface-area solutions and still greater energy density.

How Energy is Consumed

The amount of electricity used per year by humanity is in excess of 20 petaWatt hours per year. The US uses about 20% of that, and China uses another 20%. This doesn't include the energy produced by internal combustion engines, or by burning coal, wood, and kerosene for heating. When all energy consumption is added up, total annual consumption is 474 exaJoules.

It is interesting that world energy consumption decreased 1.1% in 2009, due mainly to economic downturn in North America. But that trend doesn't seem to be a continuing story, since in 2010 world energy consumption grew about 5%. In particular, China's energy consumption did not decrease in 2009, and consequently it is now the world's largest energy consumer, at about 18% of global energy consumption.

What's Next?

In part 2, we will drill down farther into how energy is consumed, and discuss what we can do to cut down on energy consumption, and what is already happening in that regard. We will also discuss the thorny issues surrounding fossil fuel usage. Also, the carbon footprint of energy production and consumption will be discussed. Which energy sources have the smallest carbon footprint? It's not obvious at all.