Steam turbine mid game viability

[Wiother]

I am quite new to the game (few hundred cycles), yet I saw a lot of videos, tutorials and read a lot of posts.. just like all of us.

tl;dr: Steam turbines with aquatuners mid game without super coolant as base cooling solution - is it worth it?

The other day, I ran into mid game with my colony (about cycle 100) and found volcano quite close to my base and got thinking about steam turbines. After some search, I found this post about the fair usage of the steam turbine for the means of cooling through aquatuners. Trying to make no-exploit, no walk-around solution for the steam turbine in the early-mid game for the purpose of cooling the base (the volcano heat energy production is a different topic) and go through the numbers. The goal is to consider self-sustaining cooling room design with as little energy input as possible. This whole post is theoretical calculation of minimal energy input for steam turbine cooling.

I am aware of door pistons, drip-cooling and blocking intake of the turbine solutions. I understand people using them, especially the piston solution as it just suplements piston part to the game. I just don't find them clean..

Our system (all credit goes to Nickerooni as the original poster of the design) consists of:

• One steam turbine
• Pre-cooling to recycle heat into the boiling room (crude oil is a good choice with high capacity and temperature range enough to sustain operation at around 425K where is the steam turbine output)
• A cooling loop of one aquatuner right below the steam turbine that condensates cold steam
• Liquid pump connecting the Condensation room and Boiling room
• A boiling room where pre-cooling system recycles the heat and thus boils the water back to steam.
• Single tile wide tunnel from the boiling room to steam heating room

 

1. dT=75K - Let's count the theoretical minimal drop in temperature 500K->425K and thus consider
2. m=10000 g - full turbine continuous operation so we have as much energy output as possible.
3. c=4.179 DTU/g/K - Heat capacity of water
4. eta=1 - efficiency of the heat recycler, that is cooling from 425K after turbine to 373K on condensation is recycled in the boiling room to heat it up.

In such case, the minimal cooling of the turbine and thus the minimal heat we need to put in is Q=dT*m*c=3132000DTU, respectively power(heat) input if taken per second. Now the same equation for aquatuners:

1. dT=-14K - aquatuner cools the liquid by 14 deg
2. m = 10000g - we assume the highest efficiency, that is a full liquid pipe
3. c = 4.179 (pwater) or 8(supercoolant) - pwater as the temperature of the medium is sufficient and has the highest early-mid game heat capacity from available liquids, supercoolant for late game comparison.

This leaves us with cooling power of one aquatuner  of Q=dT*m*c= -584640 DTU and heats the steam around. For supercoolant the value is Q= -1120000 DTU Thus, in completely isolated system in equilibrium (all heated up already, no heat excapes through walls). We need 6 aquatuners with pwater or 3 aquatuners with supercoolant late game to compensate the cooling. Each aquatuner is currently at P=1200W one liquid pump of P=240W, one aquatuner for the condensation and boiling room loop P=1200W and finally the turbine output P = -2000W. Thus the net power input needed to sustain this system is P=6640W for pwater aquatuners and P= 3040W. And that is at best when we dont consider real operation above 500K, thermal losses through walls, liquid water drop below boiling point depending on materials, etc. I neglate these losses with the aquatuner in condensation room which has actually some heating atop.

So my question is - is steam turbine cooling system too high-energy demanding until late game or did I make some miscalculation?

Note: About the materials - all is within operation for steel aquatuners(~600K operation, 100K safe from operation - in reality the operation has to be higher to operate) and few more parts, otherwise gold amalgam, ceramics. Quite easy to get solutions in this phase of game.

[wachunga]

You did make a trivial typo miscalculation with 4.176 in your math instead of 4.179. But the thing you are missing is that a turbine doesn't have to run 100% and very likely won't. It deletes a truly astounding amount of heat, more heat than you are likely to need deleted. And you don't need aquatuners for every source of heat you want to delete. Rockets, metal refinerys, glass forges, volcanoes all produce high temperature heat that doesn't require an aquatuner to dump into the turbine.

But let's say you only want to use aquatuners. You should be looking at the cooling per watt. The numbers of watts needed to run a turbine 100% is irrelevant. A water aquatuner is equivalent to 48.755 wheezeworts. That's 25W to reproduce the cooling of a wheezewort. Or 164W to reproduce an AETN. This would be a great deal if the fixed temperature outputs of sieves and carbon skimmers and oil refinerys didn't exist.

[biopon]

Well if you want the turbine to run as much as possible (which in the early-mid game can be desirable due to the power produced) you can block a few input ports on it to reduce the amount of cooling provided. But as wachunga pointed it out above, you don't need the tuners to "compensate for the cooling", you're doing all this for the opposite to happen: get the turbine to compensate for all the heat. And that's easy enough, even with 4 blocked ports, because the fixed output temp on the turbine provides an almost limitless cooling power, as long as your source (tuner in this case) can withstand higher temperatures.

[EnergeticSecret]

one solution to this problem is by stacking steam turbines. this way you only need to condense steam once for multiple turbines.

based on your calculations 3 stacks needed with chilled supercoolant as condenser to gain net energy. but of course you can always stack some more.

[avc15]

If your goals are: minimal heat waste, no space age materials, no perpetual waterfalls or gas layering trickery, and an actual boiler/condenser, and you want it to be power positive -

You need a heat recovery boiler. And this is a thing you can build in the game. It should be a double tube heat exchanger, not a tube and shell heat exchanger.

One of your assumptions is that you cool the exhaust using a coolant fluid and an aquatuner. Aquatuner gradually pumps heat out of your 425K exhaust until it condenses at 373k (and in reality it takes more cooling than this)

Then you're using a heat source (volcano?) to boil your water.

Try this instead.

---

You have a reservoir of boiler water at ~~97C, and exhaust coming out at around 425k (actually a little more).

Use the exhaust to preheat your boiler steam, then boil the feedwater. In that order because, counter flow heat exchange. At the same time, precool your exhaust. Only force condense the leftover precooled exhaust.

If your design is good, preheated steam (before you ever draw heat from a volcano) will come out of your heat recovery boiler at above 410k, and precooled exhaust will exit your heat recovery condenser at below 380k. So you can be looking at ~107C -> 97C or so (it's impossible to make it perfectly 100C/100C) times the mass flow rate of exhaust. 

If you make a good heat recovery system, the steam genny could be built with no advanced materials, even without steel.

It's all theory, though, because when I built it I ran out of time. Mine kept destabilizing and shutting down. And using various "tricks" I mentioned before, you can make a much simpler and highly efficient build, so this build I'm talking about would be nothing more than a curiosity. (door pumps, escher water pumps, pumping gas using gas layers - I won't say the word exploit here because that's debatable on each count)

[Technoincubus]

They are so hard to etablish that I usually never bother with them