Monthly Archives: May 2008

LED Lighting

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I’ve added a new section to the sidebar for LED lighting. While LED lighting is presently very expensive, there are some applications in which it is preferable to compact fluorescent and ultimately LED lighting promises to be much more efficient, provide better color rendering, have a much longer life span, and be less expensive than compact fluorescent without any toxic mercury (but there are other toxic substances such as arsenic, although generally in significantly lower quantities).

We use a tremendous amount of energy for lighting. Compact fluorescent greatly improved lighting relative to incandescent lamps and even somewhat over the larger fluorescent tube lamps. Incandescent lighting tends to turn between 3-5% of the electricity it uses into visible light while compact fluorescent tends to turn between 15% and 20% of the energy consumed into visible light.

LED stands for light emitting diode. It is a solid state device that acts like a solar cell in reverse. LEDs in their pure form produce a very narrow band of light frequencies so they have a distinct color such as red, orange, yellow, green, blue, etc. White LEDs are being manufactured for illumination purposes but these actually are usually blue LEDs with a broadband yellow phosphor that converts a portion of that yellow light into a broadband yellow spectrum light. Single color LEDs can be made with efficiencies that very closely approach 100%, but white LEDs currently in production are usually on par with compact fluorescent efficiencies with 15-20% efficiencies though some of the very best approach 30%.

This method of making white light actually is spectrally very sparse and renders colors very poorly. A better and potentially much more efficient method is to combine a red, green, and blue led into one unit. This can produce a LED which has spectral output in all the same energy bands that our eyes have receptors and thus can render colors much better. Until recently, ultra-bright and efficient red and blue LEDs existed but ultra-bright green LEDs were not as efficient and limited the overall efficiency of a LED light using this technology. However, recent advances now make it possible to make an ultra-bright and efficient green LED but this type of RGB LED isn’t yet in wide production.

So while present LED lighting tends to be insanely expensive, only about as efficient as compact fluorescent, and with a similarly icky color rendering index, the potential exists and has been realized in the lab, for LED based lighting that is nearly 100% efficient or about five times more efficient than compact fluorescent, and that has an excellent color rendering index. This is about as large of an improvement in efficiency over compact fluorescent as compact fluorescent is over incandescent lighting. Hopefully we will see these get from the lab into full scale production and costs drop out of the stratosphere soon.

LED light lifetime also tends to be much better than compact fluorescents, with typical ratings from 30,000 to 70,000 hours, however, this is actually much better than the numbers indicate because of the difference in the way lifetimes are rated. Compact fluorescent lamps are considered “dead” even in the absence of complete failure when their output drops to 50% of their new output. LED lighting is considered “dead” when it’s output drops to 70% of it’s new output. If LED lifetimes were rated at 50% instead of 70% output, they’d be much longer. Also, compact fluorescents frequently do fail outright rather than just dimming, but in the absence of some external abuse, LED lamps rarely do, they just get progressively dimmer with age. Lastly, the rate that LED lamps dim is dramatically lower when operated at less than 100% rated output power and their efficiencies are generally higher at below 100% rated output power.

One additional difference, compact fluorescent lamps perform poorly in cold temperatures owing to incomplete vaporization of mercury used in the arc tube but LED lights are generally more efficient at lower temperatures. LED lifetimes are longer at lower operating temperatures.

Category: Future

Inexpensive Solar Panels

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Recently, I added a section to the sidebar of Solar Panel sources at prices of $4 or less per watt. A recent search turned up a few more sources under the $4/watt figure, one at $3/watt though the $3/watt panels were CIGS technology which, although less expensive, is both less efficient and shorter lived than silicon panels, particularly mono-crystalline solar panels.

When you look for Solar Panels, the most common types you will find are mono-crystalline, poly-crystalline silicon, amorphous silicon, and CIGS (Copper Indium Gallium Selenide) (Cu(In,Ga)Se2) [Thanks to the anonymous commenter who pointed out my error.]

Of these mono-crystalline panels are the most expensive; there are even more expensive multi-junction solar cells and solar panels manufactured but they are so expensive that they are generally reserved for space applications where the power-to-weight ratio far outweighs the additional expense given the huge cost of getting something in orbit.

Mono-crystalline solar panels are generally the most expensive solar panel designed for terrestrial applications, however, they are the most efficient single junction panel and they have the longest lifespan. Mono-crystalline solar silicon panels will generally provide efficiencies of 15-19% and lose less than 10% of their power production capability in thirty years. You should look for panels with a glass, not plastic face because plastic will discolor over this time frame and reduce efficiency.

Poly-crystalline silicon solar panels are less expensive than mono-crystalline panels but also have lower efficiencies, generally in the range of 12-15%, and poly-crystalline silicon solar panels will usually lose about 10% of their capacity in the first couple of years. Thereafter they will generally remain stable for decades.

Amorphous silicon solar panels use a thin film of silicon deposited on a substrate such as steel or glass. Those that use steel as a substrate are flexible. They typically have low efficiencies ranging from about 6% to 10%. Although they cost less to produce, market demand is presently much greater than supply because their flexible nature allows them to be used in products where other types of solar cells can not be used, such as roll-up portable battery chargers, and at present their retail cost does not reflect the lower cost of production and in fact tends to be higher than other silicon panels. Because many different substrates and disposition methods are used to produce these cells, little is known about their long term stability and it is likely to vary widely with the substrate and manufacturing process used.

CIGS technology solar panels are very inexpensive to produce, but they have lower efficiencies and deteriorate faster than other solar panel technologies. Although they are often advertised as having a lifetime of twenty years, they really haven’t been around long enough to know what their long term performance will be like. Although much less expensive to produce than silicon panels, the present market saturation conditions tends to keep their retail prices at around 75% of those of polycrystalline solar panels. However, as production is ramped up they have the potential for producing power at well under $1/watt and at that rate, a shorter lifetime and lower efficiency may well be an acceptable trade-off for much lower costs in many applications.

Category: Future

Why A Nuclear Iran?

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While the United States continues to threaten Iran, Iran really has no choice but to pursue a nuclear program. In doing so, it risks possible destruction from a US or Israeli attack, although I am convinced what’s left of our own country would be left in shambles as well, but if it fails to do so it’s citizens ultimately will face starvation and Iran will still face possible US or Israeli attack.

Iran is highly dependent upon desalinated seawater to provide water to grow crops to feed it’s 66 million people. Easy to get at oil is a valuable commodity and Iran’s oil fields are already in decline. Nuclear energy is one option, and probably the most economic option, for providing the energy necessary for desalinization of seawater on a large scale.

When you’ve got a whack neighbor like Israel that feels obligated to regularly bomb all of it’s surrounding neighbors, and that neighbor has a nuclear arsenal; then unless you enjoy glowing in the dark, some kind of deterrent is really necessary.

When you’ve got another whack foreign power that eyes your oil reserves and has demonstrated no qualms about killing and maiming millions to obtain them, again some kind of deterrent is necessary.

President Mahmud Ahmadi-Nejad is regularly misquoted as calling for the destruction of Israel; this quote is taken out of context, and actually he is quoting former leader and setting himself apart. If you dig around the net a bit, you can find the speech in question.

I really wish we could drop the war mongering and get on with life. It is really in everyone’s interests for these countries to modernize; fundamentalism does less well in a modern society.

Category: Future

War and Greed

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If Iraq were producing oil at pre-war levels; an additional million barrels per day would be on the market, more than 1% of the worlds total production. Even given existing demand, we would not have an oil shortage, oil would likely be under $40/barrel.

However, if we wouldn’t have invaded Iraq; demand would be considerably less because the US military is one of the largest oil consumers in this country. All of those Hummers running around Iraq don’t run on solar power.

Our dollar would be worth a lot more, our military would be prepared to deal with real threats, and our economy would be in much better shape.

Middle-East oil is attractive to oil companies because it’s relatively inexpensive to produce, when they don’t bear the cost of a military operation to invade a country. The war only increases their profits.

It is in our interests not to depend upon foreign sources of oil. There is no reason that we should because we have ample resources in our own country. If the cost of war is factored in, developing them would be much more cost effective both in terms of dollars and environmentally. War is hell on the environment.

I believed that when the millennium rolled over; it would be the start of a new age and we would abandon war as an energy policy. Now that we’ve had an eight year demonstration of just how much of a failed policy that is I hope that we can get on with a better policy and take a different path.

Category: Future

Connecting The Dots…

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Often partial solutions to our problems are presented on the Internet but nobody puts the pieces together. Recently, I have focused quite a bit on the energy issue, and I have found that solutions abound, but the political will to implement them is lacking, or they appear uneconomical because they are, by themselves in fact uneconomical.

A good example of this is wind power penetrating the grid at more than about 20%. By itself taken in isolation, with all other variables ignored; more than about 20% seems impractical because of the variability of wind. But taken with other solutions the picture is quite different.

Our existing electrical grid is mostly an AC grid, the east and the western grids aren’t substantially connected, and overall it’s inefficient, unreliable, and at capacity straining to meet ever growing demands.

If this weren’t the case; if we modernized our electrical grid adding east-west ties and converting all spans longer than 300km to DC transmission, first, doing this alone would be like adding 15% additional generating capacity to the grid without any additional pollution because we could cut the losses from around 17% to around 2%. Moreover, efficient east-west transmission would allow us to distribute the peak load across the time zones requiring less peak capacity and making more efficient use of the capacity we already have, above and beyond grid losses.

If we can utilize geographical diversity with wind generation, something only possible with the modernization of our power grid; then the total capacity available from wind power never falls below about 1/3rd of peak capacity, and then we could, if we choose, simply overbuild capacity and supply our entire electrical needs from wind alone. I’m not advocating wind alone, ideally we’d use a mixture of renewable sources, solar, geo-thermal, ocean-current, ocean-wave, tidal, ocean-thermal, various forms of hydro (there are forms that can capture energy from the movement of river water without dams), etc.

We could generate all of our electricity by wind if we so choose simply by building 3x as much capacity as we need and modernizing the electrical grid. But there is a snag, wind, presently the least expensive method of generating electricity, less so even than coal now, would lose it’s attractive economics if we had to overbuild by 3x AND if there were no market for that peak power.

Add in some other technologies, for example, we can take electricity, carbon dioxide, and water, and using one of three processes, we can make an alcohol called butynol which can directly be used as a replacement for gasoline in ordinary gasoline cars. Butynol actually has tremendous advantages over gasoline. Butynol produces only 3% of the hydrocarbon emissions, almost unmeasurable carbon monoxide emissions, and greatly reduced nitrous oxides relative to gasoline. It also produces slightly better fuel mileage and power, greatly reduced acidic blow-by products (thereby enhancing engine life) and less waste heat (also enhancing engine life).

We can make butynol from electricity, carbon dioxide, and water by one of three methods. There exists a kind of reverse fuel cell that was recently invented that uses a catalyst in the presence of electricity to convert carbon dioxide and water to butynol. That is one method; it’s a method that from what I’ve read Richard Branson paid to have developed to produce butynol as a renewable jet fuel. However, there are two other methods also that can be used, carbon dioxide can be electrolyzed into oxygen and carbon monoxide, the carbon monoxide can be mixed with steam to form “process gas”, and then in the presence of catalysts, this can be used to create a variety of useful hydrocarbons including butynol. Lastly, electricity can be used to create sufficient heat to disassociate carbon dioxide into carbon monoxide and oxygen and then the same process that follows electrolysis can be used. The last process has been demonstrated on an industrial scale, I’m not sure if the first processes have made it out of the lab, but they have at least been demonstrated in the lab. Using the latter two processes it is also possible to make synthetic diesel.

If use the electricity generated during times when there is excess capacity to create butynol, we can replace imported oil used for gasoline and diesel, while at the same time providing a market for the peak electrical production, thereby allowing wind power to be economical even when capacity is overbuilt, and we create a market for the carbon dioxide generated by existing coal and gas fired plants instead of just releasing the carbon dioxide into the air. When the butynol is burned it will release carbon dioxide, but this is displacing oil that would have been burnt, so the net result will be a reduction in carbon dioxide and if we can bring enough renewable electricity capacity online to eliminate the need for fossil fueled power generation, then we can continue to make butynol by sequestering carbon dioxide directly from the atmosphere, thus making the process a closed loop resulting in no net carbon dioxide increase.

Any one of these elements by themselves may not be economic; but they are all mutually synergistic and implemented together they could eliminate our dependency upon foreign oil first, and later eliminate our dependency upon fossil fuels (or for that matter abiotic oil) entirely.

We should be doing this, and we should not be doing it ten or fifty years from now, we should be doing it now.

Category: Future

Bush Asks Saudi’s to Produce More Oil

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If the Saudis could produce more oil, why would they? $129/barrel is a good thing from their perspective. So they offered to increase by 300,000 barrels/day, a drop in the bucket, which essentially amounts to “no”. I don’t think the Saudis can produce significantly more oil. Ghawar is Saudi Arabia’s largest oil field, accounting for approximately 70% if it’s daily output. In 2001, the Saudis started injecting seawater to maintain oil pressure. Now the water cut from many of the wells is on the order of 55%. A point will be reached when the energy required to extract the oil is so great that it will become impractical to continue producing oil from this field and the rate that the water cut has increased suggests that that point is not far away.

There are newly discovered fields offshore in the Santos basin that may eventually replace some of the lost production capacity in Ghawar but this reservoir, like the other newly discovered reservoirs along the South American coast and in the Gulf of Mexico, requires drilling an average of 22,000 feet and the cap consists of 5500 feet of salt which is highly corrosive at the pressures that exist at that depth. This presents significant technological challenges that neither Brazil or Mexico appears ready to tackle.

At the current market rate you had better believe that the Saudis are producing every drop they can. The current high market prices have produced a wealth of new oil discoveries and there is no doubt in my mind that supply will catch up with demand eventually but these types of deep ocean reservoirs typically take 5-10 years or more to develop so this is not going to provide any immediate relief from high oil prices.

The only thing that is going to lower the price of gasoline and other oil derivatives is if we reduce our demand and increase our supply. We have the means to do both but apparently not the political will.

The real solutions are going to come from a variety of sources but all of them take time to bring online, so in my view, we should be pursuing all of them as fast as we can.

There is enough surplus energy on the electrical grid at night to power our daily commute, all that we need to make this possible is a practical plug-in hybrid vehicle. While GM has a concept car called “The Volt”, like most GM concepts it will probably never see production. Their present claim is that the batteries aren’t available in sufficient quantity yet. Meanwhile, a Chinese company is making plug-in hybrid vehicles with a 60 mile all electric range using their own proprietary lithium-iron-sulfide battery technology. I would bet that if GM was given sufficient financial incentives, we could see that plug-in hybrid introduced in the near term.

Even if GM produced an affordable plug-in hybrid tomorrow, people don’t replace their cars overnight, especially in a depressed economy, but it would be a start; lowering the prices, and it also would be an exportable technology which would help reduce our trade imbalance and strengthen the dollar. To the degree which it does reduce oil consumption, it will place downward pressure on the price of oil and upward pressure on the value of the dollar.

If we’re going to make the transition to clean renewable energy we need to find a way to do so that won’t totally destroy our economy and we have to find ways to minimize economic opposition to this transition. To this end, I think we should invest in coal to liquid technologies, and in places where we have natural gas production without an economical method of transporting it, natural gas to liquid. Then, as we displace coal and natural gas from electricity production, we can use this coal and natural gas to make liquid fuels and displace imported oil.

We have to stop the economic hemorrhaging, the money leaving our country and the value of our money from going down the toilet, in order to have the capital resources necessary for new energy infrastructures.

Doing this would reduce net carbon dioxide emission because we wouldn’t be burning that imported oil anymore; and we’d be using coal much more cleanly rather than burning it in a power plant, because the process of converting it to a liquid fuel would remove contaminants like mercury, arsenic, sulfur, radium, etc, and that material would no longer go up a smoke stack and be disbursed across the countryside. Instead, those materials can be recycled and used by industries that need them.

As coal production is replaced by renewable sources such as wind, solar, geothermal, and other renewables, we can start using surplus electricity to produce liquid fuels, especially butynol which can be used as a direct replacement for gasoline, and removing carbon dioxide from the environment in the process.

We really need to ramp up our domestic energy production now; it’s the only thing that we can do that will leave us with enough of an economy to make a transition to renewables and to prevent starvation as food shortages and the inability to move foods to the market, will otherwise price food out of the reach of many people.

Magic financial manipulation won’t save us from $10/gallon gasoline, the only thing that will do that is to produce enough energy to meet our demands, and the only thing that is going to stop the rapid decline of the dollar is a correction of the huge trade imbalance and national debt that we have. Becoming self-sufficient for our energy needs is a necessary prerequisite for peace in the middle east. As long as we are dependent upon the middle east for energy, the financial effects are going to provide the incentives for war. Nothing is a larger environmental or economic disaster than war.

National security also demands energy self-sufficiency. If we are dependent upon the middle east for fuel, pretty soon we’re going to find it difficult to even fly our planes. There is no doubt in my mind that this fact will not be lost on China and Russia, not to mention many other nations that we’ve given good reason to hate us. When they realize that all that is necessary to cripple our military is to disrupt an 8,000 mile long supply line of oil tankers, they are going to feel emboldened. The only defensive option that would leave us is the nuclear option, and a nuclear exchange with Russia would be pretty much the end of civilization.

Category: Future

Energy Costs – Gasoline Prices

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Our energy woes aren’t going to resolve themselves unless we continue to let them escalate until enough of us die off that demand is brought within the constraints of supply. That would be an extremely painful solution to the problem but it seems to be the default solution and the one that politicians are heading towards. Without major input from us, it’s not going to get better.

The demand for energy from China and India is going to continue to grow, and it must, because only by eliminating poverty can we hope to have a humane solution to overpopulation. In developed countries, people naturally have fewer children, in fact, excluding immigration developed countries have negative population growth. The same thing needs to happen in Africa as well, Malaria and AIDS need to be brought under control, the food and water issues need to be resolved, and when these things happen we’ll see a similar growth in demand for energy.

In the United States we could totally eliminate our need to import oil by simply addressing waste in the electrical generation and distribution system. What does electricity have to do with gasoline? Well, everything!

50% of our electricity is generated by coal, 20% by natural gas, 19% by nuclear, 7% by hydroelectric, 2% by petroleum, and approximately 2% from solar, wind, and other renewables (excluding hydro-electric).

Coal and nuclear energy, which together make up 69% of the energy supply, can not be throttled down at night. In the case of coal, the thermal mass of the system is just to great to change the energy production rate rapidly, and in the case of nuclear, it takes too long to bring the reaction back up after shutting it down. The electrical demand for energy is much lower at night, so the excess produced is dissipated as waste heat, pollution is generated, but the energy is just wasted.

There is so much wasted energy from these sources at night that they could power our entire daily commute eliminating the need to import oil. We import about the same percentage of oil as goes into powering our daily commute.

If we could take that wasted energy produced at night, use it to power our commute during the day, we would eliminate the need to import oil; we’d go from having a trade deficit to having a trade surplus, we’d see the dollar strengthen, we’d see our economy improve; and we’d eliminate the financial incentives for going to war in the middle east. We’d eliminate all of the carbon dioxide from all of that imported oil being burned, without adding anymore from power plants, because we’re just using energy they’re already producing that is being wasted.

How can we do this? There are a variety of ways we can do this; the one that you hear talked about the most is plug-in hybrid vehicles. These are gas-electric or diesel electric hybrids with enough battery capacity to cover the normal commute and the ability to recharge off the power grid. Problem, nobody in the United States is producing them at present. Chevrolet has a concept car called, “The Volt”, which they claim will be in production in 2010 but not at present because they claim adequate batteries aren’t available.

Yet, the Toyota Prius is readily converted to a plug-in hybrid using existing battery technology. The Prius has a “stealth mode” button that is enabled in other countries but not in the United States that stops the car from using the gasoline engine so that one can drive short distances on electricity alone. The Prius also has space for a second battery pack. Plug-in hybrid enthusiasts have been enabling this button on US models, adding a second battery pack, and adding an off-the-grid charger to convert these cars to a plug-in hybrid.

China has an automobile manufacturer making plug-in hybrids for domestic use in China, a company called BYD makes a plug-in hybrid vehicle that can go sixty miles on electricity alone. BYD developed a rechargeable lithium iron phosphate battery system for their vehicles. They plan to market these vehicles to Europe and the United States in 3-5 years. Meanwhile our automobile industry continues to lose money and lay off workers because they can’t sell the SUV gas hogs they produce when gas is $4/gallon. Why isn’t Detroit producing these? Why does GM drag it’s feet saying that the battery technology is not available when amateurs are converting Prius cars using existing battery technology and China’s BYD is manufacturing and marketing plug-in hybrid vehicles based upon their own battery technology?

Plug-in hybrid vehicles are only one way to use this surplus energy. Another method is to convert surplus electricity into liquid fuel. How can we do this? There are two methods I am aware of for taking electricity, carbon dioxide, and water, and making a 4-carbon alcohol called butynol which unlike Ethanol and Methanol, has an energy density nearly that of gasoline, a road octane of 104, and can be burned directly in unmodified gasoline engines. Because of the characteristics of the fuel, it actually gets better mileage, produces more power, and reduced emissions by 97% relative to gas, and the lower peak cylinder temperatures and lower partial combustion products, longer engine life can be expected. One method involves a kind of reverse fuel cell in which electricity and a catalyst drive a reaction to produce butynol from carbon dioxide, water, and electricity, the other method is to electrolyze carbon dioxide (yes, you can do this) to produce carbon monoxide and oxygen. The carbon monoxide is then mixed with steam to make process gas which can then be converted into a number of useful hydrocarbon liquids, including butynol.

This process CONSUMES carbon dioxide making the butynol fuel! So if we located these adjacent to coal fired plants, we could take that carbon dioxide and instead of pumping it into the ground, which is long term a really bad thing to do for reasons I mentioned in another post; we can make it into fuel! So this is a way that we can shift the EXISTING automotive fleet to using surplus electricity at night and this wouldn’t have the limited range of plug-in hybrids since butynol can be distributed the same way that gasoline is. Because butynol is not hydroscopic, unlike ethanol and methanol, it can be piped through the same pipelines used to move oil distillates.

Now, long term we want to get off of burning hydrocarbons entirely, except those that are created by taking carbon dioxide out of the air such as biomass, or butynol produced this way. We have plenty of sources that we can exploit. There is enough geothermal energy available in environmentally non-sensitive areas of the western United States that we could power our entire electrical grid this way. Presently however wind is the most economical, but wind is not constant. Now if we put these electricity to butynol plants in place, and then just overbuild wind capacity we provide a market for the times when wind produces a surplus by using that surplus to make fuel. Thus making butynol from electricity can shift the commute to using presently wasted energy, provide a market for carbon dioxide and surplus wind power allowing wind power, which is the least expensive source of electricity, to fulfill a much larger percentage of our energy needs.

There is another way butynol can be produced, and that is by using concentrated sunlight to break down carbon dioxide to produce the same process gas, which ultimately can be made into butynol and other hydrocarbons.

These things can only be ramped up so fast. We need to be doing everything we can to encourage them. We also must stop the outflow of capital from this country to the middle east. To that end, in the short term we need coal-to-liquid plants. If we did this concurrent with displacing coal generation with solar, geothermal, wind, and other renewables, it would result in less resistance from the industry to the transition, and at the same time provide more capital for the implementation of new clean and renewable technologies. We can not afford to allow our economy to go down the tubes any further because it will make conversion impossible and in the end all we’ll have is a lot of people starving to death, riots, and war.

Our current energy situation is so dire that we really need to exploit all our alternatives to the max, but even so it may not be enough to keep our farm equipment moving producing food and our distribution network distributing it, and get us to work and back. We need to do what we need to do in the short term but we need to focus on the long-term.

To this end I believe we should look at adding an import duty tax on oil of around $20/barrel, and then taking that money and using it to develop all of these alternatives as fast as possible.

Another area we could obtain a huge amount of energy from, and that would also increase the degree to which we can depend upon wind and solar, would be to drastically modernize our grid system. Presently, long distance transmission lines lose an average of about 17% of the energy put into them. Nationwide this results in a loss of approximate 10% of our electrical production capacity.

The particular modernization that we should consider is converting all AC transmission lines that are longer than 300km to DC high voltage transmission lines. Doing that would cut that 17% loss figure to 2-3% by eliminating radiative losses which are the largest portion of transmission line losses.

Switching to DC transmission eliminates electromagnetic radiation from those AC transmission lines which is a leukemia hazard to anyone living near them. Low frequency magnetic fields have been determined to have carcinogenic effects. One suspected mechanism is that a low frequency AC magnetic field causes ions to spiral as they pass ion transport channels in cell walls reducing their ability to cross these channels. Drugs which reduce ion transport have also been shown to increase cancer rates. For many people, particularly those living in houses with older wiring where the source and return path are not always cabled together, the magnetic fields generated inside are often far higher because you are very close to them. Never the less, there is a statistical correlation between leukemia and living in proximity to AC high voltage transmission lines. DC high voltage lines do not radiate and thus eliminate both the majority of their power losses and this cancer threat.

Switching to DC eliminates susceptibility to space weather. Space weather, solar storms, induce very low frequency currents in long distance transmission lines. In AC lines, the transformers have very low impedance to this low frequency current and the current causes the transformer core to saturate. This results in the destruction of the transformer and failure of the transmission line. In DC transmission lines, this same current is induced, but simply slightly increases or decreases the voltage and the far end and the inverters compensate in real time and no damage results.

Switching to DC eliminates cascading failures. In an AC line, if one source of capacity is lost or load increases, there is no way to limit the load on the line except through load shedding which may or may not happen fast enough, and if it doesn’t happen fast enough, failures result. When one line goes down, it increases the load on the next, phase and voltage fluctuations result which increase the load even further, and additional lines go down. In this way, a localized failure can cascade across an entire grid. But with DC lines, the inverter technologies limit the power in real time and keep the phase constant, so no cascading failures result.

Switching to DC adds significant capacity in two ways. In an AC transmission system, the peak voltage is 1.414 times the RMS or average voltage. So a line designed to carry 500KV AC has to have insulators designed to carry 1.414 times that value or 707KV. So we can take an AC line designed to operate at 500KV and operate it at 707KV DC, at the same current that is a 141% improvement in transmission capacity. But it gets even better, because on long transmission lines, the factor that limits current is heat induced sag. When wires are warmer they expand, when they expand the total length of the line changes and that changes the phase relationship of the voltage at the far end. Out of phase power just heats the wires and so current has to be limited to values that are much lower than the line is physically capable of carrying. With DC transmission, the phase is determined by the inverter and is independent of the line length, and thus sag induced phase shift is no longer a limiting factor. Of coarse the current still has to be limited to values above which sag would represent a physical danger to the line but this value is significantly higher. So switching to DC transmission increases both the current carrying capacity and the voltage capacity of the line.

For new lines, the costs are less for DC lines than AC lines for distances longer than 300km. DC lines require less right-of-way because there is no AC magnetic field radiation. They require only two conductors instead of three (or in some cases six). For a given conductor power and insulators they can carry significantly more power. These factors all combine to make them much less expensive for distances greater than 300km.

Reducing the losses substantially while increasing capacity makes it cost effective to transmit power over greater distances and allows for greater geographical diversity. This in turn allows wind, solar, and other variable sources to contribute to a greater share of the load because geographical diversity can be used to advantage. When the wind isn’t blowing in one location, it is blowing somewhere else. Currently in the United States, we have an eastern grid and a western grid. We should add DC interties and make it one grid. Peak loads occur at different times because of the different timezones, so full east-west connectivity would reduce the peak-to-average load ratio allowing us to use our generating capacity more effectively.

I know that I dwell on this particular subject a lot but it is of major importance and getting next to zero attention. The deregulation of the power industry has resulted in a situation where nobody wants to contribute the maintenance and upgrading of the power grid and this is absolutely critical towards the end of solving our nations energy issues and adopting renewable clean energy sources on a large scale. Our congressman appear to be completely ignorant of these issues, it’s up to you to educate them!

Category: Future

Fox News Bill O’Reilly Lies About Reverend Jeramiah Wright

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Fox News has portrayed Reverend Write as a hateful, bigoted, and anti-American. They have used out of context sound bytes towards this end. In the interest of accuracy in journalism, I located this video recording of Reverend Writes sermon after 9/11 so that you can here the sound bytes in context.

Online Videos by Veoh.com

Now that you’ve heard it in context, I will add that I think his message, that hatred begets hatred, terrorism begets terrorism, is right on. I believe that the Bush administration has lead us down the wrong path, a path that leads only to misery, death, and destruction. You’ll note that I’m a white guy, this isn’t a black-vs-white thing that Fox is trying to make it out to be, it’s about a path of love and respect for life and God’s creations verses a path of hatred, death, and destruction.

Category: Future