Making pyrolysis economic

Pyrolysis, the anaerobic heating of hydrocarbons such as wood, old tires, used engine oil, plastics, tallow and so forth, needs to be economic for it to be undertaken. Below are some suggested ways to increase the financial feasibility of pyrolysis.

 

 Energy conservation

Pyrolysis needs heat energy to cause the various long chain materials to break ('crack', in petrol-chemistry terms)  and the applied heat must be at a temperature of about 500⁰C. But, of course you don't want to be heating the great outdoors.  That is a waste of energy/money.  Super insulation is needed so that you only use  the amount of energy needed to break the bonds. An insulation material that comes to mind is the Aerogel that was used to protect the shuttles during re-entry but cost and availability might be a barrier.

Source of energy

Clearly the energy to heat the retort must be renewable.  Energy must come from hydro, wind, geothermal or solar sources.  Renewable energy continues to go down in price as the hardware to produce it becomes less expensive. There are a couple of possibilities.  With the spot-price-silliness that we have in New Zealand, electric energy is very cheap when it is in excess.  Either the pyrolysis unit can operate, only when energy is cheap or cheap energy can be bought and stored in a mega battery to ensure the continual operation of the pyrolysis unit.  

 

It may be worthwhile for the pyrolysis unit to own it's own renewable energy kit and thus be always paying the wholesale price.  This 'kit' continues to decrease in price.  With a battery as well, excess energy can be sent to the grid when spot prices are high. 

Energy is likely to be one of the largest running costs in a pyrolysis factory.  

 

Externalities

Many  waste streams  can be pyrolyzed to produce either liquid fuels or easily compressed and liquefied fuels.  Many waste streams are problematic if not disposed of somehow.   

There is now a cost to send waste to land fill and a land fill trashes beautiful pristine wild areas which are then no longer an asset to the community.  

Some wastes are direct health hazards such as the leaching of material from them into the ground water or as breeding grounds for mosquitoes (tires).  As the world warms, tropical mosquitoes that carry a range of very nasty diseases will be moving poleward.   

Many pyrolyzable wastes are a fire hazard and the by product of  burning some of them creates the toxic, carcinogenic, dioxane, and fine particulate material.  If they are sent overseas, the receiving country may simply dump them into the ocean.  There is no need to describe why ocean dumping is problematic.

    

The point is that the pyrolysis unit has to be credited for the financial cost it mitigates when a solution is not found for that particular waste and/or for the present cost of taking care of the waste.   Government action may well be necessary to ensure this.

By products

Depending on the feed stock, there are various valuable by products of pyrolysis.

Wood

The by product of wood-pyrolysis is charcoal.  Charcoal can be bagged and sold for barbecues or can be incorporated into agricultural soils, earning carbon credits.  See Terra Preta

 

Plastic (clean or contaminated)

No by products result from the pyrolysis of plastic.  It all converts back into alkenes and alkanes.  The alkenes can be converted into the more useful alkanes by saturating the double bonds with green hydrogen.  Petro-chemical engineers have methods of either bonding low molecular weight fractions into larger molecules or, on the contrary, cracking long molecules into smaller ones to get more of the desired fraction.

Electronic equipment

The pyrolysis of electronic equipment results in a metal rich ash.  As battery recycling ramps up, this ash could likely be sent to a battery recycling facility for the separation and recovery of these metals.  This sort of ash is a far richer source of metals than any natural ore although it is a rather challenging mix.  At present, waste circuit boards are sent overseas for the recovery of their metals.  Most of the weight of a circuit board is plastic.  With pyrolysis, you don't send the plastic  saving on weight and hence expense.

Used tires

By products of the pyrolysis of tires are iron, sulfur and carbon black.  Sulfur can be converted into sulfuric acid, using the oxygen which is a by product of the Hydrogen which has been produced for saturating alkenes.  Sulfuric acid is a very valuable product used in a plethora of chemical processes.  Carbon black is used in air and liquid filters, black paint and in the production of new tires and black plastic.  The iron is sent to an iron refinery where it is combined with iron ore in the smelting process.

Used engine oil

Used engine oils are very variable.  For instance some of them have additives of materials such as molybdenum sulfide.  Presumably this, and any other similar materials would remain after the pyrolysis of used engine oil.  In addition, there may be a small concentration of metal from the engines.  But I suspect that well north of  99% of engine oil should convert into the usual pyrolysis products.  The ash could probably be combined with the ash from electronic equipment and sent to a battery recycling facility.

Tallow

Tallow should not have any by products and rendering is not necessary.  It can be directly pyrolyzed.  However, if tallow is converted into biodiesel  instead of using pyrolysis, glycerine is a by product.  One has to work out if it is worth while to build a separate facility for the chemical conversion of tallow to diesel or to simply pyrolyze this waste stream.

Side economic benefit

If this whole process is kept in the eye of the public as it proceeds, it would seem likely that the petrol company responsible would gain a greater share of an ever diminishing market for petroleum products.  Parts of the output of pyrolysis can be mixed into conventional petrol and diesel, making them 'greener' and done through already existing distribution channels.

Petrol station conversions

 

The demand for petroleum products (LPG, Gasoline, Diesel and lubricating oil) is not going to suddenly stop.  Second hand ICE (Internal Combustion Engine) cars are going to be around for a long time and they will become very very cheap as the demand  for them wanes.  Everyone will want an electric car but the cheapness of ICE cars will persuade many to continue to use them.   And there will always be "petrol heads" who just love their ICE cars.

 

However, the demand for petroleum products will start to decrease and it will be a one way trend.  What do "gas stations" do.  They work on very small margins and large volumes and on having a monopoly on the fuel we need for transportation.  It doesn't take much of a decrease in their sales to make them a stranded asset.

 

Clearly, if they want to continue in business, they have to become energy providers rather than petroleum providers and allow us to charge our battery cars at their facilities.  They have a problem here that all sorts of other companies have realized that if they have a charging station, it will attract customers to their premises to shop while the car is being charged.  Charging stations are springing up at super markets, restaurants and other businesses. 

 

The petrol companies need other streams of revenue.  A couple come to mind.  Already many 'gas stations' have stores and restaurants connected to their petroleum outlets and I suspect that they make more money on these than on the sale of petroleum.  Just here where I live, one gas station showed real initiative when it started to sell really large ice cream cones at cost.  Suddenly their business boomed and the kids pushed Dad into stopping there to fill up.

 

When you are charging your car, no matter how fast 'fast charging' gets, it will always take more time than to fill up the tank of an ICE car so you have a little time on your hands.  It is likely that smart gas stations will expand the goods that can be purchased at their stations.

 

But there is another revenue stream that could be attractive to a petrol station that is also a charging station.  Mega Batteries.

 

If a lot of cars are charging at the same time, especially if they are all fast chargers as seems to be the trend now, it will put a huge demand on the grid.  The whole grid will have to be upgraded to avoid burning out the wires at peak times.  that is unless the petrol stations install a mega battery.

  

Let's say for the sake of the argument a petrol station installs a one mWh (mega Watt hour) battery.  A typical car of the future will have, say, a 100kWh battery.  A fully charged 1mWh battery could therefore charge up 10 cars without needing recharging.  Batteries are now being developed based on Li that will be able to charge right to the top and be used right to the bottom without damage.  Anyway,why such a large battery, Isn't it a waste putting in such a large capacity you might say.

 

Well no.  Mega batteries by themselves are ridiculously profitable.  Look at the Hornsdale example.  It is rumored to have paid off its $66m(Aus) cost in three short years by buying power when it is cheap and selling it when it is expensive.  Better still, for the Hornsdale site, it is part of a wind farm so they  store power when it is being generated in excess of demand rather than having to feather the wind turbines.

 

This points up the next profit generator for the gas stations we are converting.  They should install solar panels on every surface they have available.  Most of them have a large roof over their petrol pumps and the roof of the adjacent building where they sell pies, ice cream, bread and milk. 

 

A petrol company with many gas stations could become a major player in the energy supply of a country.  One of our NZ petrol companies has upward of 250 stations.  With a one mWh battery at each station, they become one of the largest battery operators in the world and as a bonus it is distributed storage.  They become a large peaker plant and benefit from our insane spot price system.

 

There is also a possibility that negotiations with existing power distributors might result in less expensive power to charge the mega battery since the power distributor avoids the need to upgrade their grid to cater for a whole bunch of fast chargers all operating at the same time. The only really grunty cables that are needed are those from the mega battery to the charging points, not the whole grid.

And here is one more revenue stream generator.  As ICE cars age, there is, going to be, for a while, an ever increasing demand for mechanics.  The cars will be getting longer and longer in the tooth and need ever increasing maintenance.  For a while, a connected garage, the way it used to be, will be a real money spinner.  Mind you, at some point this will fade as electric cars take over.  The smart operator will make money in this golden period and then get out of this part of the business.

 

It is going to be a difficult time for 'gas stations' unless they innovate and become energy stations.

Open letter to NZ power companies.

 

        An open letter to NZ power companies

 

Just curious.  A rhetorical question, if you like.  Why is it that none of the power companies and none of the wind farms have installed mega batteries.  The 100mWh Tesla battery at Hornsdale in Southern Australia has paid off it's total capital costs in 3 short years.  I've never heard of such a profitable investment.  Now virtually all the income is pure profit.  In addition it has greatly stabilized the voltage and frequency of the grid it is part of and has reduced power prices.  They are now installing more batteries, more or less doubling their capacity.

For new wind farms, I wonder why they don't put in a mega-battery first before they even have the first wind turbine up and running.  With our crazy spot price system, it would seem likely  that they would have started to make a profit right off, buying low and selling high.  When the turbines are working, they can, of course, store any excess power they generate instead of having to feather the the turbines.  Mega batteries basically constitute a peaker plant*.

*A power plant that is only used when power demand is unusually high.  They are highly uneconomical but are needed to ensure a constant supply of electricity regardless of the demand.

From the customer's point of view, if power companies had mega batteries, the power companies could stop being so twitchy about their customers installing solar panels.  They could give the customer a decent price for the power that he sends to the grid, say 75% of the price that they charge the customer for power he takes from the grid.  This would eliminate the need and the motivation for the customer to go off grid and/or install his own batteries.  The customer foots the capital cost for the generation infrastructure (panels) and the power company gains all this extra generation capacity for free.  It is a win win all around.

 Lithium is not the only game in town.  For instance, there are the ZnBr plating batteries and the liquid metal batteries using Ca and Sb.  Both have the distinct advantage of not degrading over time and both can be fully charged and discharged without damage.   They also don't lose their charge if left fully charged.  They don't have quite the cycle efficiency of Li batteries but are a tad better than pumped storage. If you go to youtube and type in 'Just Have A Think Iron Batteries' you will see another innovation that, if it is all it is cracked up to be, will revolutionize renewable energy.  Then there are a range of redox batteries using the different oxidation states of Fe or V.

Why are you power companies so slow off the mark. You could be creaming the profits while at the same time serving your customers, something that is somewhat lacking at present.  I think I know what the answer is.

You are making lovely wind falls when the spot price peaks.  When enough mega-battery capacity is installed there will no longer be these wind falls.  Mind you the first adopters will really cream the profits.

Greening the Sahara Desert

There is a fascinating possibility that the Sahara desert could be vegetated and brought back to the state it was some thousands of years ago.  Paintings on cave walls and rocky overhangs shows a rich fauna of the type we only see today further south in Africa.  In addition we only see very old trees of some species in the Sahara.  Seeds from these trees don't germinate now due to the dry conditions.  The trees put down roots during a wetter period and have followed the water table downward as the Sahara dried out.

  'Greening' could be achieved if we could induce the monsoon to re-establish itself over the Sahara.  Such an engineering/agricultural project may sound like pie in the sky but there are reasons to believe that it might be possible.  But first, what is a Monsoon.

 

We are all familiar with the famous Monsoon over India but this is just one Monsoon among many.  A monsoon occurs in the summer when the sun heats the land enough to cause the air above it to rise and suck in moist air from over the ocean.  It helps if this air is sucked up and over rising ground and it further helps if there is some moisture in the air that is already over the land from, for instance, land vegetation transpiration. In addition, vegetated land has a lower albedo than bare sand and rock.  In other words, if the land is already vegetated, a monsoon is more likely than if the land is bare.  The following map shows the location of 

monsoons in the world.

Air can only hold so much moisture and the amount is greater for warm air than for cool air.  The air as it flows over up-sloping land, expands, cools (Appendix 1) and reaches the dew point which is the temperature where the air is fully saturated.  Further cooling due to further increase in altitude and the air becomes super saturated and the moisture begins to condense out of the air in small droplets.  Now another effect increases the rise of the air.

 

The phase change from water vapor to water releases a huge amount of heat.  (Appendix 2).  This keeps the air from cooling and makes it more buoyant with respect to the surrounding cooler air.  This powers it upward to release more moisture.  You begin to get those huge cumulus clouds.

You might think that the air with a suspension of tiny droplets of moisture (cloud or fog) would be heavier than the air from which it formed and you would be correct.  It is just that the effect of the release of latent heat, as water vapor changes to water, is way stronger than the effect of suspended water droplets in the air.

 

The key to the whole system is sufficient summer heating to get the air rising in the first place and sucking air over the land from the sea.

 

You would think at first glance that the Sahara would be ideal.  After all, it is very hot in the middle of the Sahara.  Apparently it is not hot enough.  In fact the Albedo (reflectivity)  of the Sahara is rather high.  Not as high as for snow but the light colored sand reflects a lot of the incoming radiation from the sun, back into space.  In addition, with clear sky at night the heat accumulated during the day, radiates straight back into space.  Here is where humans can have an effect.

 

Across the Sahel, the area to the immediate south of the Sahara, a number of countries have decided to plant a band of trees.  This is exactly what is needed.  When you have trees, the light and other wave lengths of EM radiation from the sun, hits the trees and some is changed into heat.  The rest is reflected.  Because of the physical form of the trees,(vertical surfaces) reflected radiation is likely to then hit another surface, either another tree or the ground.  From there another surface, each time with more of the original energy changed into heat.    If you look from space, a tree covered area looks dark.  In other words it has a low albedo.  The question is, can we plant enough trees to have a sufficient effect.

 

You can think of trees as a greenhouse solid (appendix 4)

 

Trees also have the second effect mentioned above.  They transpire moisture into the air so there is more water vapor available for condensation and the release of latent heat. 

Water is interesting in another context.  Carbon dioxide absorbs part of the spectrum of heat that is radiated from the ground and re-radiates it in all directions including sideways and downward but it misses a portion of the infra-red spectrum.  Water vapor intercepts some of these frequencies and so increases the green house effect.

 

If you look at the above map, you will see that a monsoon occurs to the south of the Sahara.  Perhaps all we have to do is to continuously widen the band of trees toward the North and the Monsoon will follow.  It might even be worth while to use precious fresh ground water or desalinated water to ensure the survival and growth of the trees as we gamble on a much greater return of water from an established monsoon.  Apparently there is a huge reservoir of ground water under parts of the Sahara but is not being renewed by rainfall.  We can either use this water for present agriculture until it runs out or we can use it to grow trees, gambling on the fact that we can re-establish the monsoons for a much greater return of water to the Sahara and a replenishment of the ground water.

 

There are other factors that likely play a part in a lack, at present, of a monsoon over the Sahara.  As mentioned, at night, heat is radiated through the clear skys into space.  Consider a canyon in the desert.  It will have heated up during the day (although less than open sand since part of it will have been in shade during the day) and when night comes, heat will be radiated from it's surfaces.  On the open desert, pretty well any direction heat is radiated is out into space.  However in a canyon, much of the radiation from the bottom and sides will hit another surface and be absorbed to be re-radiated.  A canyon is something of a heat trap and I'm sure desert dwellers have discovered this. A canyon would be an ideal location to hunker down for the night.

It is not unusual to find ice in the open desert in the morning in, say, a cup of liquid that you have left on the surface.  This, despite the fact that the day was blistering hot and will be so again today.  Basically, the desert looses all that lovely heat it accumulates over the day, during the night.  You see where I am going with this.

If you have established a forest, even with trees quite spaced out, radiation from a warmed tree or from the warmed ground is likely to hit another surface with less of it being radiated out into space.  In the morning, it will be warmer in a forest than in the open desert.  The more heat retained, the greater the chance of a monsoon. 

 

A forest causes more heat to be accumulated during the day and less heat to be lost at night.

The heating during the day starts from a higher temperature in the morning. 

Another  effect occurs if the increase in air humidity results in clouds, even thin cirrus clouds.  At night, this will hold heat in by reflecting it back down to the earth, resulting in over all warming. Clouds at night are probably the major factor amongst all the above in retaining the heat during the night.

 

Then we have Green House Gasses.  Already, the concentration of Carbon dioxide, methane, oxides of nitrogen and a few others are warming the atmosphere by absorbing heat radiation from the ground and re-radiating it in all directions.  But water vapor itself is a green house gas. The following chart shows the absorption spectrum of Carbon dioxide and water vapor.  Note that water vapor absorbs infra-red wave lengths that Carbon dioxide misses.

 Then there is the added effect of water vapor on the buoyancy of the air.  Just thinking about the weight of water compared to the weight of air, you might expect that humid air would be heavier than dry air but it is exactly the opposite.  When you dissolve a salt such as sodium chloride into water, the ions of sodium and chloride fit in between the water molecules.  The total volume of the solution is less than the volume of the water plus the volume of the dry salt.  Gasses are not like that.  Every gas you have in a mix contributes exactly it's volume to the mix.  Water vapor is lighter than air so the mix will be lighter, the more water vapor that is in the air (appendix 3)

 

There is a technology that could help.  There exists a technology to grow vegetables in tunnel houses, using water from the sea or from an underground source of alkali, or other, otherwise unusable water. Besides vegetables it results in the production of brine and fresh water.  The brine must be piped back to the sea or  into evaporation ponds.  If the brine is evaporated, the accumulated salt is either used if it has a market value or is periodically collected up and transported to the sea.  The fresh water is used to grow the vegetables.  The excess fresh water flows down into the ground, creating a lens of fresh water around the tunnel house.  Once there is fresh ground water, vegetation begins to develop around the tunnel house and this helps with the above mentioned second effect that promotes the formation of a monsoon. Namely the increased humidity of the air.

It is important to have a rich organic soil in the Tunnel house with some UN-oxidized carbon.  Such soils scavenge and retain nutrients from the irrigation water so that pure fresh water peculates down into the ground.

Of course, once the monsoon has started, it tends to be a self reinforcing process as more and more vegetation develops naturally.  It is a gamble but I think it will be worthwhile to use precious ground water or even desalinated water to establish a forest across the south of the Sahara and to continually widen it in the hope that it will result in a much greater return of fresh water from an established monsoon.  It would probably take a cooperative effort by all the Northern African countries.

 

Something else worth mentioning is the effect of an ever warming ocean.  When the ocean is warmer than the surrounding land, air rising over the ocean pulls air from the land.  You have the typical evening and night off-shore wind.  And the air over the ocean contains lot's of moisture so the latent heat effect can further strengthen the pull of air from the land.  On the other hand, the warmer the ocean, the more moisture in the air above it.  If the warming of the desert can be made sufficiently strong to overcome the pull from the sea, there is more water vapor available for a monsoon.

 

One sad but inevitable effect of the success of this action would be on the Amazon Jungle.  A jungle, left alone, is very good at recycling it's nutrients.  It appears incredibly rich, just like a coral reef but this is an illusion.  At present, the Amazon receives a small but much needed dose of additional nutrients from the dust blowing off the Sahara.  If the Sahara is 'greened' that will stop.  The Amazon will cease to be 'the lungs of the world' and will stop sucking up carbon dioxide.  However, it looks like the Amazon is finished anyway due to man's activity.  The Sahara would likely take on the roll of the Amazon if the Monsoon was re-established.

Appendix 1

When air expands it cools.  The amount of water vapor air can hold depends on it's temperature.  Pressure decreases with altitude so a body of air blowing upwards over a mountain range, for instance, expands, cools and is capable of holding less and less water.  If it has been saturated by blowing over an ocean, it will be super saturated as soon as it begins to rise over land and will give up it's water as precipitation.

Appendix 2

It takes a massive amount of heat to evaporate water.  When water vapor condenses, it releases this same amount of energy.  I'll use calories to explain this since in this one instance, it is easier to understand than using the modern SI units.  A calorie, (small 'c')* by definition is the amount of heat needed to raise one gram of water by one degree centigrade.  Thus to raise a gram of water at zero degrees to the boiling point at 100 degrees, it would take 100 calories.  To evaporate this same gram of water would take 540 calories.  In other words, enough heat to raise the temperature of that gram of water from freezing to boiling 5 times and then from zero to 40 degrees.  This heat is given off when water vapor condenses into water.

*  A large Calorie (Capital C) is defined as the amount of heat needed to raise one kilogram of water by one degree centigrade.

 

Appendix 3

The molecular weight of air is an weighted average between Nitrogen (28) and Oxygen (32) so, to a first approximation, is about 30.  The molecular weight of Water is 16 for Oxygen and 1 + 1 = 2 for Hydrogen.  So water vapor is 18/30 x 100 = 60% as heavy as air.  The more moisture in air the lighter it is.

Appendix 4

Green house gasses keep the earth warm.  When the radiation from the sun hits surfaces, it warms them.  They then radiate longer wave lengths of EM radiation.  Green house gasses absorb specific wave lengths of this longer wave length energy and radiate it in all directions.  So the effect of green house gasses is to retain heat in the air.  Trees do the same.  They absorb radiation and re-radiate it in all directions.  A forest intercepts much of this radiation and re-radiates it in all directions.  You can think of a forest as a green house solid.

Why not Hydrogen

Hydrogen is really a non starter for domestic vehicles. I'll explain why in a bit. But don't dismiss Hydrogen all together. It is a very useful chemical.  It can be used for super high temperature plasma arc welding.  Experiments are also in the pilot plant stage to use hydrogen to refine iron ore instead of using Coke.  If the hydrogen is produced by electrolyzing water instead of reforming methane, then there will be a significant reduction in our carbon foot print.  There are many many other uses, too numerous to include in this blog.

In addition, the production of Hydrogen by the electrolysis of water, if done correctly also produced Oxygen which has a plethora of uses in our modern society.

However, hydrogen can not compete on a cost basis or energy efficiency basis, with simply charging a battery.  To charge a battery, you generate power (renewably, of course), transmit it across existing power lines and charge your battery.  Let's take a fairly bad case and say we loose 6% of the power in transmission.  So 0.94 of the power gets through.  We then charge the battery in the car and use this power to drive the car.  Taking a worse case scenario, we get 80% or 0.80 of the power we put into the battery out of the battery.  Multiplying these two figures together we get  0.752 or 75% of the energy generated is useful energy in an battery-electric car.  Of course the situation improves if you have your own solar panels and charge your car right beside them.

Let's look at the situation with Hydrogen.

First you have to split water by electrolysis.  We will ignore the steam reforming of Methane since it produced Carbon monoxide.  In other words it has a significant carbon foot print.  The present efficiency of water hydrolysis is about 80%.  In other words, the energy content of the hydrogen produced is 0.80 of the energy used to produce it.  If we are talking economics rather than energy efficiency, it should be noted that, if done correctly, the by product of H2 production is O2, a very widely used chemical in a modern society.

Then you have to compress or liquefy the hydrogen.  To compress Hydrogen takes up more energy.  It takes about 38% as much energy as was used to produce the hydrogen.  In other words it's efficiency i 62% or 0.62.   Without even shipping the hydrogen, we are down to 0.80 x 0.62 = .49 ie 49% and we also have to multiply by the efficiency  of an internal combustion engine using hydrogen or a fuel cell(34% and 60% respectively).  Let's ignore using hydrogen in an internal combustion engine as it has poorer efficiency than using a fuel cell.  

At this point we are in the same situation as an electric car running on a battery.  The electricity produced by the fuel cell is used to power the electric motor of the car.  

 So the best case is with a fuel cell and we multiply 0.49 times 0.60 = 29% compared to a battery which gives us 75% from renewable energy source to the electricity fed to the electric motor of a car.  Note that I have taken the very best figures I can find for the use of Hydrogen and the worst figures I can find for a battery car.

We also haven't taken into consideration the energy or economic cost of transporting the Hydrogen to the hydrogen station.

How about if we decide to compress and cool the hydrogen to liquify it.  We start with the same efficiency of electrolysis to produce the Hydrogen of 80%. It takes about 30% as much energy to liquify Hydrogen as it took to produce it.  Therefore, it is about 70% efficient.  0.70 x 0.80 = 0.56 or 56%.  Looks promising, no? But our troubles are not over.  Liquid Hydrogen at one atmosphere outside pressure has a boiling point of minus 253C.  And wherever you store the liquid Hydrogen, even in the arctic it is a relatively  hot day outside.  And we still have to multiply by the efficiency of a fuel cell (60%) so we have 0.56 x 0.60 = 0.34 or 34%. Liquid hydrogen must either be allowed to evaporate to keep it cool or refrigerated down to minus 253 degrees C.

Liquid Hydrogen has a whole raft of other problems associated with it's need for very well insulated containers, the fact that is slowly boils off and needs the hydrogen gas to be re-liquified or you must simply wear the loss and it's danger in an accident as liquid hydrogen will blast freeze anything it touches.

Hydrogen is a very valuable product for  a wide range of applications, just not for domestic transportation.

https://www.youtube.com/watch?v=AoXJYPfag1I

energy

Why Impeach Trump[

 A few of the members of the United States Congress have said it is just petty to impeach Trump.  After all, he will be gone in a few days.  Just let him go.  Let's look at some of the implications of impeaching or not impeaching.

1/ American politicians blather on about America being a country of laws.  In other words, personal interest, wealth, position and so forth do not influence the outcome of a trial.  All is fair in the land of the brave and the home of the free.  Of course this is complete nonsense but, at least verbally, this is what politicians aspire to.

  If some one else had committed a crime, and, say, promised to leave the country, there would be no thought of letting him go scott free.  He would be brought up for trial and either convicted or freed.  

The same should apply to Trump.  In fact, reversing the idea of a blind fold over the eyes of the  justice lady who holds the scales in her right hand and the sword in the left, the punishment should be greater for a person in great responsibility who flouts the law.  Convicting Trump for the great finale of his disastrous 4 years in office is simply the right thing to do.

2/  You, the members of congress, both in the house of representatives and in the Senate are sending a message to the American people which will be recorded in history for all time.  You are saying either that firing up a mob to march on the very core of your democracy for completely specious, selfish, self serving reasons is either OK or is not OK.  

Micky mouse regimes rarely have an orderly transition of power.  With all the abuses in the American democratic system such as voting suppression, few and far between voting stations, denial of voting for registered people, use of voting machines, gerrymandering and so forth, the one ray of light in this whole sorry morass you call democracy was your orderly transition of power.  Now even that has been threatened.  The world should send observers to the USA to monitor your elections.  By not convicting Trump you send a message not only to your people but to the world that the last remnants of democracy in America is now gone.

3/  On a more prosaic note, some corporations have announced that they will no longer support the election campaigns of any member of government that votes against impeachment.  There is a very tight correlation between the amount of money a candidate can raise and his chances of winning the vote.  There are rare exceptions but the correlation is far greater than is ever seen in social sciences. 

 If corporations carry through in sufficient numbers, you are toast and this is where the public can have an effect.  We, the people, simply boycott any corporation that supports corrupt politicians that refuse to convict Trump. This will threaten the destruction of your system of lobbying and vote buying, the way you enrich yourselves when in office and your cushy jobs when you leave office.

4/  If you do not convict Trump, he can continue to disrupt the government over the next 4 years, basically campaigning to become president in 2024,  This is the worst nightmare possible for the American people and what little is left of American democracy.  If found guilty in the Senate, it is much more likely that attorneys general  of the federal government and of various states will move to convict him on many other crimes he has committed.  They will not be afraid of his revenge when he again becomes president. By convicting Trump you open him up to a complete examination of his corrupt business practices.

Just a final thought.  As strange as it seems, given the present voting in the Senate, it is in the interest of the Republican senators to convict Trump and in the interest of the Democrat senators to acquit him.  If he is acquitted, he will continue his destruction and splintering of the Republican party over the coming 4 years and then run again in 2024.  The Republicans then have two choices.  They either take him as their candidate or allow him to run at the head of his so called Patriot party.  On the Republican ticket he will continue the destruction of the GOP and of America.  On his own ticket, he will split the vote on the right and allow the Dems to sail through the rift between these two parties.

Clearly, if we completely ignore the fact that another 4 years of Trump would be a disaster for America, it is in the interest of the Dems to acquit Trump.