Steam Generator

Quote from Thunderdark

if reach 100C every sec you get 1000-2000 Steam on 100 Heat

Thunderdark, as you know, the heat capacity of the boiler and its water tank is not the only thing affecting how fast steam is generated. That should be mostly dependent on the enthalpy of vaporization of the water.

I say should because in real life, water has a heat capacity of 4.18kJ/kg.K. Heating 1kg of water from 25C to 100C therefore takes 314kJ. Water's enthalpy of vaporization is 2260kJ/kg. Thats 7.2 times larger. It takes 7.2 times more heat to vaporize the water than it took to heat it up.

In IC2E, the heat capacity of water is 40HU/mB.C. Heating 1mB of water from 25C to 100C therefore takes 3000HU. After looking at the boiler class file, I found the enthalpy of vaporization is currently 480HU per mB. That's about one sixth! Clearly in IC2E the rate that you can create steam is far more dependent on heating the water. The actual vaporization takes very little energy, and this is quite unlike real life.

This raises a couple of points:

1) If my boiler is constantly being fed fresh water, then at steady-state it takes 3480HU to make a bucket of steam. The rate that I can produce steam with a Liquid Heat Exchanger is about 29mB of steam created per tick (on average, as steam is always made in 1000mB increments). This is already hard to manage, because Buildcraft wooden pipes can only extract at 10mB per tick.

2) If my boiler is not being fed water, and I have waited for the water to reach 100°C, then it only takes an additional 480HU per bucket of steam. With a Liquid Heat Exchanger that's about 208mB of steam per tick, which is practically impossible to manage with buildcraft pipes. I'd need to use a much more powerful pipe like EnderIO's pressurized pipes, which can pull at 200mB/t. I really don't like this. Even if I switched to a Electric Heat Generator with only one coil, that's still over the 10mB/t that a buildcraft pipe can deal with.

3) The very long heat-up time of the boiler is not very fun. Thanks to your recent change, we can easily change heat capacities in the config file (yay!) which makes the waiting less boring. However we can't increase the heat of vaporization to compensate, and steam production volume is again very hard to deal with.

It would be nice if we could also change the heat of vaporization. However, I think it would be far, far nicer if the volume expansion of water to steam was much less. I realize that in real life, steam expands about 1700x (at atmospheric pressure, of course), but such large volumes of steam don't cooperate well with current fluid mechanics in minecraft. It would be a little realistic to assume that pipes are pressurized, and steam is quite compressible. Could you change the ratio to ~100 or less?

These are great points and i feel that should be respected.

But since these are balancing issues i think the priority should be first implementation and then later some balance update.

if you are using wooden pipes to pull liquids you are limiting yourself
emerald pipes are capable of pulling 40 mB/t.
I do admit that BC's pipes are limiting, and that is a constant source of discussion on the BC forums. but you can do better with BC pipes.
and personally, I feel that RC's boilers will beat IC2's steam generator for making regular steam.
especially since it is MB and auto outputs the steam into any acceptable container.
at the very least your steam, generator should do the same, which makes a lot of sense, especially if you pressurize the steam and reduce the expansion, which if you are going for powering a steam turbine makes a ton of sense.
steam turbines run at about 3000 RPM and the main line pressure varies depending on the size, but can exceed the kPSI range. some even have a low pressure section that operates below atmospheric pressure, leading directly into a condenser. Many in the electrical generation reheat the steam to increase efficiency. Nuke reactors actually run cooler than other fired plants so the turbines are run at a lower RPM.

Well, I could also propose something.
With all I've read, I think that as soon as you use water in a boiler or anything, it becomes calcified. Would it be possible to use for example water from rain? As this water has already evaporated, therefore leaving all the ions that it was carrying, it shouldn't calcify your boiler. It would need another machine (maybe not a machine: iron rusts, but more a plastic tank, or anything) that would only run when it rains.

Also, I don't know what the boiler runs out of, maybe EU or lava or combustion or I don't know, but it could be nice to have a block that can heat up the water thanks to the light of the sun. It would work more efficiently in deserts biomes, as long as the solar boiler is placed with a reasonable amount of light. Though, it would not be able to run thanks to the light of the torches.
I've got an idea for the recipe: use dark dyes instead of coal dust and a pipe instead of the machine block in the solar panel recipe.

Personally, I would say that using reactor hot coolant is the best way to produce steam. I don't know why, maybe because it is cooling down the reactor and because it doesn't consume lava when you could use it for something else.

i edited my post but you replied before I was done.

I just noticed: if you compress the steam, it will be likely to condense into hot water. See that, it shows what's the state of water depending on the pressure and the temperature.

The only reason power plants use water these days is because it is safer. They would run much more efficient if they used some chemical that could be heated to several hundred degree and then cooled back to room temperature.

If i have the time i'll do some research and give you some numbers about the difference between water(steam) and other fluids.

Also, nuclear power plants use heavy water that is composed of 2 atoms of deuterium (isotope of Hydrogen) and oxygen. Heavy water aborbs quite well free neutrons released by Uranium fission.
EDIT: Sure, it adds to the security level.

And of course, let's not forget molten salt cooled reactors, which have gained a lot of media attention lately. Whereas sodium can be very reactive, molten salts are much more stable (although potentially corrosive).

Yeganer, I would not say that water is necessarily safer than other liquid coolants. Water may not be very reactive, but most water-cooled reactors must operate at very high pressure... PWRs more so than BWRs (150atm vs 75atm). That amount of pressure is costly and dangerous, as the vessels and piping are under much more stress. A piping failure will usually cause the cooling water to flash to steam, which could lead to a loss-of-cooling meltdown. A meltdown involving steam can actually get hot enough to dissociate the water into hydrogen and oxygen, which can lead to a hydrogen explosion (such as the disaster at Fukushima). Nasty. The low pressure requirements of sodium and molten salts is one of the most attractive things about them.

Back on topic. I've been playing around with the Steam Generator in a legit survival world, and I'm finding the cost of distilled water to be very high. If it takes 3500HU per mB to vaporize water, then a single bucket of distilled water effectively costs over 3.5 million EU. Since coolant is now made with lapis dust and distilled water, it is proving to be very costly to create enough coolant to even think about running a reactor. I've also become painfully aware that Overclocker Upgrades take three coolant cells, which is over 10 million EU. Without a reactor, that's quite a lot of power to scrounge up.

When thunderdark gets around to balancing passes, I think I'll be arguing in favor of much lower steam costs overall.

EDIT: Just noticed build 535 and the different recipe for coolant. Hehe...

the steam generator should be like the RC boilers, auto output steam to legit containers/pipes.

another thing about the molten salt reactors is they don't have to use uranium, they can use thorium. thorium requires no processing, decays via beta radiation which is stopped by clothes, and is the third most abundant radioactive element on the planet....one downside, weekly on site reprocessing of the fuel, which can yield uranium. Plus thorium reactors take 1/100th the foot print of a uranium reactor.

water is used due to its massive thermal capacity. it is actually the highest for the most common liquids. sure it has issues, but far cheaper than some exotic liquid that may or may not be any safer under the same circumstances. (4.1813 J/(g K) for water, anti-freeze is actually less than that of water 54% for ethylene glycol, which can burn, propylene glycol varies 50% @ 0C to 70% @ 100C at SAP)

Quote from Chocohead

It already auto-outputs steam. What more do you want of it?

someone said they were having to extract the steam via BC wooden pipes....from that I made the mistake in thinking it didn't auto output.
this is def one of those machines that should be a MB structure. different sizes would produce different amounts at different efficiencies. almost should be like RC boilers but use electric heaters instead of fireboxes.....though maybe not....maybe just electric tank blocks as you can submerge the electric heating elements in the water.

Quote from Chocohead

It already auto-outputs steam. What more do you want of it?

Oh, I didn't realize that. I was a little annoyed about its lack of upgrade slots for an ejector. Whoops

i was about to say, i ran a gold pipe directly from it. only problem i have is that it outputs to ALL sides(asfaik), requiring a regulator(eu) or a feed pipe that is never empty. i have not tried feeding from below, and if memory serves, all ic2 machines generally don't output to pipes below.