Beer is important Beer is as important to 1632 Germany as water is to a fish. It is the all-purpose beverage, one of the few liquids that will generally not give you some sickness after ingesting it. At least as long as it is not consumed in excessive quantity. Prior to refrigeration, beer could only be brewed until February or March, and then restarted in the fall. Wort cooling (an important step in the brewing process) could not be accomplished, as there was no supply of cooling that occurred naturally during those times of the year.

Equipment was idle for parts of the year, not making any beer or money for the owners. As soon as down-time brewers hear about the magic process of refrigeration, there will be a stampede to acquire this technology. This "new" technology, combined with a better knowledge of yeast and its influence on the fermentation process is revolutionary.

Down-timers do not yet understand yeast and its function in the brewing process. Proper yeast fermentation temperatures are critical to a palatable beer. Up-timerscan teach the Germans a thing or two about beer. If not flavor, then technique. There may be initial issues with German beer purity laws, as they did not take into account refrigeration and forbade summer production of beers. However, those rules were changed in OTL when refrigeration became the standard. And who says that any brewer in the USE has to follow those laws? Besides, that is Bavaria, and who listens to them?

The first practical vapor compression refrigeration system (there are several such claims with many variations), was developed and installed by Carl Paul Gottfried Von Linde in 1871, in Munich. It was for a brewery. It is conceivable that the brewing industry will invest heavily in this technology. (They gave Linde 70,000 florins after only reading his research paper!) I see no reason why the same thing would not happen again in this time line as in ours. Beer is important.

The other industry that drove refrigeration in OTL was ice. There was a tremendous infrastructure developed prior to refrigeration to cut ice from fresh bodies of water, store, and deliver it to market.

Walden Pond was used as an ice harvest location. My grandmother called her refrigerator an "ice box."

Two things killed the ice harvesting. The first was the pollution that increased in ponds and lakes made the harvested ice unsanitary. The second was the advent of vapor compression refrigeration. Vapor compression refrigeration was initially used in "icehouses" where ice was made year round. Later, icehouses were replaced by the electric refrigerator, which finally killed the home ice delivery industry.

The ice making and brewing industries drove the early refrigeration market in OTL, and the dynamics will be similar in the 1632 world.

However, there is another important factor to consider that did not happen in our time line.Seventeenth-century investors are simultaneously starting the chemical industry, petrochemical industry, pharmaceutical industry, steel industry, precision manufacturing and instrumentation industries, gunpowder industry, textile industries and electronics industries, to name a few.

And every one of those industries is reliant on refrigeration in some manner. Many could not exist without advanced climate or process cooling apparatus. Some can "get by" without it for a while. Steel is a good example.

Steel? Refrigeration is needed to make steel? Well, not exactly the steel itself. But without refrigeration, there will be no basic oxygen furnaces, and therefore fewer specialty steels. Refrigeration is needed to extract the oxygen from the air, along with argon, helium, nitrogen and other gasses. We cannot even use our oxy-acetylene torches until we develop an economical process to separate the oxygen out of the air, which will generally require refrigeration. It can be made by electrolysis and capturing the oxygen from the process, but that provides wet oxygen that is more difficult to use.

Unlike OTL, the demand for refrigeration and air conditioning is going to be explosive. This dynamic economy will have a need for the existing refrigeration resources of Grantville to quickly develop the brewing, ice, and cold storage industries. This means your small home air conditioning system will be worth quite a bit, possibly more than the home and land that it services. This may satisfy a few small prototype industrial applications, or possibly the Captain General's new palace in Magdeburg, but the demand will be strong. Far stronger than the number of viable systems in Grantville.

The challenge will be to best utilize existing resources, such as home systems, supermarket refrigeration, automobiles, restaurants, slurpee machines and even home refrigerators. We will need refrigeration that can operate without electrical power, while at the same time we develop new sources of refrigeration from the 1632 tech base.

The technology will not have the luxury to gradually evolve with the industries it serviced, like in OTL.

Instead of evolving gradually over a period of fifty years, we are going to need cooling almost instantly, across a wide range of industries.

Before we get too far with all of these applications, let's learn a little more about the different refrigeration processes and how they work.

What is Refrigeration?

In its simplest form, it is the controlled movement of heat from one location to another. When you are cooling something, you are removing heat from one location, and are relocating it to another. That is why it is cool in the house and the condensing unit (the box with the fan on it) outside the house has all of that hot air blowing out of it. We are just moving the heat around. There are whole bunches of ways to accomplish this. The two main methods are vapor-compression and absorption. From there the options take off to an almost infinite number of permutations and modifications.

"Refrigeration" is the process of mechanically moving heat from one place to another. "Air Conditioning"

is controlling the temperature and humidity in an occupied space. Many times, refrigeration is used in the air conditioning process.

In the United States, the amount of refrigeration that any particular machine is producing is stated in"tons" of refrigeration. This has nothing to do with ironclad displacements, but is based roughly on a ton of ice.

In the early days of refrigeration, if you owned a theater, you wanted it cool. Early theaters (and other buildings) were cooled with ice. If you go to one of these old vaudeville houses that became a movie theater, you will notice little vents in the floor. Many times they put lighting in them now.

Underneath the rows of seats, there were blocks of ice that were placed in front of large fans, sometimes steam powered fans. As the air left the fans, it blew across the ice and cooled down. It then was discharged out of the little vents in the floor.

If you wanted to sell a theater owner a machine to take the place of his ice (which he ordered by the ton) you would want to give him the equivalent rating.

"How many tons of ice will I get out of this, Mr. Carrier?"

"This is a thirty ton machine, Mr. Ziegfeld."

This measurement was a brilliant marketing tool, which bridged the gap between ice delivery and the newfangled refrigeration process. It made the mysterious (and sometimes dangerous) technology accessible.

Today we are looking at a ton as 12,000 BTU/hr. Equipment selection is based on rate of heat removal.

And 12,000 BTU/hr is about how much cooling you will get from a two thousand pound block of ice as it melts.

How does refrigeration move the heat around?

It was discovered that if you took a high-pressure liquid, and released it through a controlled opening that allowed the liquid to flash (change from a liquid) to gas at a lower pressure, a cooling effect was created. There is a fixed relationship between the liquid state of a material, the gaseous state of a material, the pressure surrounding the material and the temperature. The manipulation of these factors creates the refrigeration effect.

By changing the pressures, a refrigerant can move between the liquid and gaseous states. The liquid, changing state to a gas, requires energy, so it grabs it from the surroundings. The net result is cooling.

How does that work? Well, it is pretty simple actually.

For example, we have a tank of liquid CO2 (carbon dioxide). It is at 1000 PSI (pounds per square inch) of pressure. When we open a valve on the bottom of the tank, what is going to happen?

Well, we will have a bunch of CO2 that starts out as a liquid, and now because of the relative low pressure, it really needs to be a vapor. The only way it will become vapor is for it to grab heat from the surroundings. Our valve on the liquid CO2 will become very, very cold as the escaping gas gets its energy from the surroundings. Voila, instant refrigeration.

This works great until the CO2 tank is empty, then the refrigeration stops. In technical language, this is called an open refrigeration system. There is no way to repeat it unless you get another cylinder of CO2. This is the same thing that happens at a higher temperature if you remove the radiator cap on an overheated engine. The typical automobile engine cooling system is pressurized to around 15PSI. That pressure keeps the water from boiling. When the cap is opened, steam sprays out of the opening, not hot water. That is why they say never to open a radiator cap when the engine is hot. With the pressure released, the 250DegF liquid is going to rapidly boil, and as it expands it sprays out the opening. It creates an instant unpleasant and burning steam bath. It is absorbing heat from the engine as it flashes to steam.

Think about an aerosol can. If you use the pressurized can non-stop, it rather quickly grows cold. When the propellant is exhausted, the process stops. This is called an open refrigeration system, because none of the components are recovered.

If the above is called an open refrigeration system, then the one that we want is going to (obviously) be called a closed refrigeration system. A closed system is one that uses the refrigeration effect of a high-pressure liquid that changes state to a gas, creates a cooling effect, and then recaptures and condenses the vapor back to a liquid as it rejects the accumulated heat. Your household refrigerator is a closed vapor compression system.

It turns out that this phenomenon works both ways, up and down. When you increase the pressure on a vapor, it will condense and release all of the heat gathered while it was changing state the first time.

Hence the warm air blowing out of the box outside the house.

Absorption Refrigeration Absorption is what is used in RV refrigerators, or in some large-scale chillers and process applications.

It has a single and substantial advantage over vapor compression. In smaller sizes, there is no need for a motor drive, only the application of heat to the system. You read that right, heat to a system to make cooling.

This chemical process was actually the first refrigeration. Thomas Cullen was exploring the nature of gasses in a vacuum in 1748. Initially, he got water to boil at room temperature by reducing the pressure in an enclosed vessel. Later, his device consisted of a pair of vessels connected with a pipe, with one vessel containing water, and the other containing sulfuric acid. When a deep vacuum was placed on the chambers, and the acid chamber was agitated, the water in the adjoining chamber evaporated and was absorbed by the strong acid. As the water changed state from a liquid to a gas, a refrigeration effect was created. The water chamber would actually freeze. When the acid became diluted with water vapors, the process stopped. Unfortunately, nothing practical was done about with his invention until 1850, when the first of the Carre brothers built a practical machine in France.

The first practical absorption machine used Cullen's sulphuric acid and water. The second brother patented the ammonia/water absorber in America in 1859. These machines made their way around the world. There were several in the United States when ice shipments from the North were stopped during the American Civil War. The southern states imported several of the machines. What is very interesting about the Carre machines is that they were able to operate with no energy input with the exception of heat, and some manual manipulation. A history described the operation of the machine in 1880 Texas as, it had "a furnace that was fired with chips and kindling wood, to heat the aqua ammonia." It was an entirely manual operation. That is important for any "off grid" operation of refrigeration. Heating andagitation of the absorbent are accomplished manually.

On a large-scale installation a perplexed operator once described it to me, as "This is impossible. Steam goes into the top of the machine, and cold water comes out the bottom!" It admittedly is somewhat counter-intuitive.

But that is basically how absorption refrigeration works. You apply a heat source to the absorption refrigeration cycle, and cooling is produced. Many smaller systems such as in RVs, use ammonia as the refrigerant, and water as the absorbent. Large-scale absorbers, that would be large enough to cool a fifty-story high-rise office building for example, are operated with water as the refrigerant, and lithium bromide (a strong salt solution) as the absorbent. These came into widespread use in the early 1950's in OTL.

I know absorption seems difficult to understand on the surface. But bear with me. Instead of a compressor inside this machine, there is a chemical reaction taking place. Ammonia is attracted to water.

The same is true for salt and water. Think of a saltshaker during high humidity. The salt absorbs moisture from the air. The result is that your salt clumps up in the shaker. The same sort of thing goes on inside an absorption machine. This chemical reaction of absorption acts as the removal process for the refrigerant vapor, sort of like the inlet of the compressor in vapor compression. The refrigerant and absorbent are then pumped to a heat source and separated. From there they return to their respective areas of the machine and begin the cycle again.

The 1911EB describes the process wonderfully. It says that the absorbent "becomes greedy" for the refrigerant. Not an exact technical description of the process, but one that certainly captures the spirit.

Continuous Process and Generating Cycle Absorption There are two main types of absorption refrigeration. There is the continuous process, and the generating cycle method. The simplest and most basic is the generating cycle method. With this, a heat source is set to the device (usually very small) once and then removed. After being heated for a period of time, it becomes "charged." The charging process separates the ammonia (refrigerant) from the water (absorbent), and allows the system to start the refrigeration process. Gradually the ammonia inside changes state from a liquid to a gas in the evaporator, creating the cold. It is then re-absorbed into the water. The next cycle (usually the next day) it is charged (heated and separated) again. Thomas Cullen's sulphuric acid device was one such system, although to charge it, the sulphuric acid was replaced, instead of being heated and separated.

For the 1632 universe, the generating cycle offers some interesting opportunities. This has a simple operation, and something the size of a small suitcase could provide refrigeration on a daily basis for food transport or home refrigeration, particularly where there is no electrical service. It opens up tremendous flexibility to the existing food transport and storage business on a smaller scale. These systems are generally very small, and can only provide a constant load. Think of them as a portable 10 pound bag of ice, which refreezes after it is used.

Unfortunately, like most things, simple operation on the surface usually means that it is more complex and well designed beneath the surface. And how would anyone in Grantville know about this process?

This process was widely used in the late 1920's as a household appliance, transitioning between theperiods where ice was delivered to homes, to modern vapor compression refrigeration. It was called a Crossly IceBall. The only way that it could be reproduced is if there is an old unit lying around somewhere, which is unlikely. It is possible that it could be developed, but the developers would need a lot of research money and time. If an old timer remembered it, just from the concept, development would be very difficult. And remember, this cannot be scaled up much beyond a few pounds of ice making per day, per unit.

Besides the internal complexity, it needs to withstand pressures of over 300PSI. This will push the envelope of construction techniques for our early modern refrigeration researchers. If the oil fields and the boiler shop can build sufficient small pressure vessels then this is a possibility. And only uses a little bit of ammonia. While this process is neat, it is doubtful that the product will be rediscovered.

The other absorption process that uses ammonia is the continuous cycle. These are the machines that the Carre brothers developed. It is also something that is familiar to the population of Grantville. This is the more common RV refrigerator. This too will be mostly a small-scale operation in Grantville for similar reasons. It can, however, develop temperatures well below freezing. There are two blind spots in this method: Internal pressures and a mix of hydrogen inside the circuit that is required for operation.

These are what are called "critical charge" systems, where the amount of each gas component needs to be exactly right in order for it to work. Very tricky, but not impossible. Again, research time and money.

However the real kicker is that these units, with the hydrogen added, operate at up to 500PSI. This alone will limit the scalability. It is not particularly difficult to build a 2" diameter pipe that will hold 500PSI. To make a three foot diameter tank that holds 500PSI is another thing altogether. Scaling will be hard, but not impossible. And there are many examples around Grantville to take apart for templates.

Hopefully, our guys at Clarence's Plumbing and Heating are very versatile, having tried to repair one of these units in the past.

Again, the above absorption methods use ammonia, and we have concerns over ammonia production, not to mention developing a pressure vessel industry.

So, how do we help the brewers and change the face of brewing beer forever? And how do we move other industries forward all at the same time?

Vapor Compression and 1632 Technology Vapor compression refrigeration has been going on in one form or another since the 1850's. Yup, that long. Which means the technology is reproducible with nineteenth-century technology. Good news for us.

As Grantville "gears down" many things that are possible to build with early- to mid-nineteenth-century technology will be possible.

This is the technology that the citizens of Grantville will be most familiar with. There is a wide installed base of vapor compression equipment in town, with many qualified people to work on it.

Okay, here are the basic parts of a vapor compression refrigeration system that we will need to build.

We have, in order of flow in the system: ? Evaporator where we are changing from a liquid to a gas, ? A compressor, which raises the pressure and temperature of the gas.

? A condenser, where our high-pressure, high-temperature gas changes back to liquid as itstemperature is reduced.

? And finally, the expansion device, which meters the amount of refrigerant liquid being fed to the evaporator.

Here is where the myriad of options comes into play. There are many different combinations of the individual pieces (evaporator, compressor, condenser, and expansion device), and they range from fractional horsepower refrigerators and water coolers, to 10,000 HP centrifugal compressors, from the size of a shoe to the size of a medium office building. The temperatures can range from 300DegF to only 55DegF. But they all work the same, and have basically the same components, arranged in the same way.

And all of these basic components are re-creatable with basic nineteenth-century technology in one form or another, and are therefore accessible to the Grantville "geared down" tech base. Basically, as the boiler and locomotive industry gears up, that technology is similar to the basic vapor compression refrigeration process. However, it will be a few years, similar to the time line that the boiler industry developed.

It is conceivable that the steam industry will gain additional financial investment by the brewing industry, or others that wish to move the technology forward. A steam condenser is essentially the same thing as a refrigeration condenser. A piston driven steam engine is essentially a compressor when turned the other way. A valve is a valve, and a pressure vessel is-you get the idea.

Refrigerants The trickiest part of the industry expansion is not necessarily the hardware. Pressure vessels and compressors are within reach. The pinch point for expansion of refrigeration beyond the existing resources of Grantville is the development of new refrigerants for absorption and vapor compression refrigeration.

Prior to the development of "Freon" in 1929, just about any refrigerant in use at the time could either explode, poison you, or both. (Freon was invented by Thomas Midgely, Jr., who had also developed tetraethyl lead as an additive for gasoline.) The industry really took off when the risk of dying from using the products decreased.

The terminology in the early days of refrigerant was "volatile fluids." It was an apt description.

Early refrigerants that were popular were ammonia, carbon dioxide (very high operating pressures), methyl amine, ethyl amine, methyl formate, sulfur dioxide, methyl chloride, blends of sulfuric acid and hydrocarbons, ethyl bromide, isobutane, dielene, gasoline, methylene chloride, and propane. Propane was marketed at one time as the safe alternative refrigerant.

The main refrigerants that came out of this period were ammonia and CO2. Ammonia is used today still in many applications, and CO2 was a prominent refrigerant of choice for marine applications well into the 1970's. However, neither of these gasses are easy to produce with the existing 1632 tech base.

Significant investments will have to be made in the chemical industries to bring these into common production.

Large-scale low-temperature refrigeration is still done with ammonia today, in food applications and iceskating rinks. It is a good industrial refrigerant, but for obvious reasons (toxicity and flammability) it is not generally used in unsupervised operation. However, ammonia is not an easy thing to make in the technology of 1632, or with early nineteenth-century technology. It can be made in small quantities from human and animal urine, but large scale production is difficult. And by 1640, we will need large quantities.

CO2 generally requires air liquefaction technology, which brings us back to Herr Linde (who invented the air liquefaction process) and the breweries. Ammonia requires complex processes to manufacture in quantity. However, ammonia has other uses. It is a fertilizer, and it helps things go boom. The "go boom"

part is important, and will drive production of this material. It makes the most sense to pursue ammonia refrigeration instead of CO2 at this time, mostly because pressure vessel and compressor construction will be simpler and lighter, and ammonia will be a priority for production.

Grantville has quite a bit of natural gas. We have another opportunity to utilize a refrigerant that is easy to distill from natural gas. Propane. As we will see below, it has very similar characteristics to the R-12 and R-134a gasses and is an excellent refrigerant.

The technology that is needed to rebuild "Freon" refrigerants, which are Chlorofluorocarbons (CFCs), is many years away. So we are going to have to utilize some of the toxic or flammable refrigerants above to drive our industries, as was done in the past. For the medium term, after existing resources are fully used up, our new refrigerants will most likely be: ? Ammonia ? CO2.

? Propane

Existing resources There is substantial availability of refrigerant in Grantville, and a fair amount of devices to use it that can be modified in a lot of ways, at least for the short term. But in the long term, as the demand for the process grows, old refrigerants will have to be rediscovered, and the more toxic and dangerous refrigerants will be pushed to the front.

The largest single quantity of refrigerant in Grantville is what is known as R-22. The letter and number codes of refrigerants have been set up over the years by the industry engineering association known as ASHRAE ("Ash-ray"). R-22 is what is used in home AC units, window units, and most of the refrigeration cases in the grocery stores at that time. We are going to assume that the stores in town were not into leading edge technology and have not changed to the non-CFC refrigerants. By careful management of refrigerant and constant monitoring of leaks, this can be expected to last in existing equipment for several years. There will probably be systems operating in Grantville well into the 1670's or 1680's if care is taken with existing stocks. It is a matter of managing the resources at hand.

Based on the grid, there will also be some refrigerant stock in town with Clarence's Heating, Plumbing, and Air Conditioning Company. They will also have vacuum gauges and a stock of vacuum pumps at their disposal. Based on the number of employees, there are at least a half dozen pumps available, as well as a dozen or so recovery tanks for storage of recovered refrigerant. They will have special tools and, more importantly, manuals for detailed repair and installation specifications on a great many varied systems. A side note needs to be mentioned here on small market air conditioning shops. In many ways, these types of contractors must be a "jack of all trades" shop. In larger markets, a contractor can concentrate on a particular segment of that market. The company that services residential units often is not set up for service of hotel ice machines and neither of them would be set up for supermarket refrigeration. They are different systems and require different tools and skills to service cost effectively. But in smaller markets, the shop must be far wider ranging, and willing to take on a much wider variety of systems than a similar sized shop in a larger area. Therefore, Clarence's group is going to be, based on its market, a highly diverse shop. A better choice than a bigger shop that only specializes in a particular market segment.

There are a sufficient amount of R-22 compressors and components to continue servicing of the systems for a number of years. With proper care, this type of equipment can run a long time. Most people do not maintain systems to the level required to achieve that longevity because it is generally not cost effective.

But when the one you have is the only one, you are very careful with it.

There are a fair number of R-22 walk-in coolers (Freedom arches, IGA, other food stores) that can be relocated to the hospital for plasma storage and drug storage. They can potentially be purchased and reconfigured for almost any other use. There are a lot of individual refrigerators in homes and businesses, so there is a long-term supply of both the cooling available in the refrigerators, and the refrigerants that are made available when units go out of service. Remember that refrigerant does not wear out, and does not have to be changed unless there is a significant problem with the system. It can be recycled and reused until it is lost.

The next largest amount of refrigerants is going to be the R-12/R-134a type that is found in cars. These are generally mutually exclusive due to lubricant incompatibilities. Using demographic data, the average number of vehicles per household inside theRing of Fireis about 1.5 vehicles per household. With approximately 1,700 households, this represents 2,550 cars and light trucks. This does not include farm vehicles and non-registered vehicles, but most of those will not have functioning air conditioning systems.

West Virginia is hot and humid; I would expect that a fair number of the vehicles in this group still have their air conditioning operational. This is open to some debate, but I am going to bet that at least 75% of the registered vehicles have functioning air conditioning. This gives us a theoretical reserve of 1,912 systems. At an average of three pounds per system, we will have a theoretical reserve somewhere in the area of 5700 pounds total of these refrigerants. This, along with the automotive AC components, is an excellent source of small-scale refrigeration equipment that is highly adaptable. This is a terrific resource to cool the operating room at the hospital for example, or support production of nitroglycerin by keeping the reaction temperatures low. It is also perfect to support beer making.

Don't scoff at automotive air conditioning as a source of industrial refrigeration. Your average sedan has as much cooling capacity as a 1500+ square foot home. And it is a highly adaptable system, capable of operating under a wide variety of compressor rotational speeds and ambient conditions. All that is needed is motive power for the compressor, which is an external drive. That means that the air conditioning system does not have the motor inside the system, like a refrigerator. It can be powered by anything. A steam engine, water wheel, electric motor; any rotational force around five horsepower.

These compressors can also be used as vacuum pumps in a pinch.

For the removal and storage of this refrigerant, the community has tools and methods in place for the job. Independent garages and the auto dealers in town will have equipment that is specifically designed to service automotive air conditioners, including vacuum pumps. In fact, it is required by the Clean Air Act, which imposed fines and other penalties for the outright release of refrigerants to the atmosphere. This was started in the mid 1990's, so all of the equipment was in place for our Grantville. Some of the automotive equipment will have minor issues of compatibility, but all of these compatibility problems are easily remedied with some creative shade tree engineering. We also have the ability to distill propane out of the natural gas that is plentiful and cheap in Grantville.

Propane is much more than a fuel. It is also an excellent refrigerant that is very close in its operational characteristics to the R-12/R134a. Recall that R-12 and 134a are used in automotive systems. At one time, propane was considered as a replacement for R-12, but it was decided that R-134a is a better choice, particularly in automotive applications, where an AC system will hold from three to five pounds of gas by weight. The distillation of propane out of the natural gas stream will provide these components with a very long lifespan.