Hello! I'm creating this thread mostly to benefit the types of people who want to optimize their mining operation as much as possible. There are already some great threads that cover the basics of how to set up a mining operation. I want this thread to help people who are planning a large scale mining operation to figure out exactly how many of each component that they need to get on site to have the optimal performance with no part being over-utilized nor being the bottleneck. I plan to start with surface operations, and expand from there assuming that there is interest. Base rules and assumptions Use engineers. You already know this if this thread interests you, but I'll include numbers to show just how much they help. Balance the drill production to ISRU consumption Create the most efficient electrical grid Maximize the fuel generated each second based on the mass of the equipment placed in situ On engineers So we all know that high level engineers make mining better, but I for one was surprised to see just how much of a difference that it makes. Lets assume we find our mining site, and it has 10% ore concentration. If we don't bring an engineer with us, we will need 100 drills all running at the same time just to supply a single ISRU converter, and the setup will draw 1530 power each second Just adding a single greenhorn engineer reduces the drill count to 20 and power consumption to 330 If we level that engineer all the way up to the max of 5, we need just 4 drills and 90 power The spreadsheet linked below shows how many drills and power you need for each IRSU based on the ore concentration and the level of engineer running the rig https://docs.google.com/spreadsheets/d/1wPRf8Pw42jjs7-f-ypjNiFG8oXsOhQ7j8CzbLIc7FeU/edit?usp=sharing Yes, there are fractions of drills listed, but chances are you will try to build a base with more than one IRSU, so you can pick a number that gives you a roughly even number of drills. Balancing Drill and ISRU production Placing the drills and ISRU in the same "craft" and balancing their outputs means that we don't need to spend mass on lots of ore storage tanks. Combining these steps also lets us eliminate the need for a ore transfer step in our supply chain, making logistics easier. All of our mass dedicated to storage (with the exception of one small ore tank) can therefore go to storing refined fuels. Power production This seems to be the most glossed over topic in most of the posts I've seen on the matter. I've seen some recommend solar, some recommend fuel cells, but few go into exactly how many are needed. For right now, if you want your operation to run both day and night, fuel cells are the way to go. If you only want to run during day time, solar power can be more efficient as long as you are no further away from the sun than Kerbin. I will be expanding this section in the near future however. Here is an example in the mean time though. (Also, the thermoelectric generator also ended up giving a worse efficiency than fuel cells in case you were wondering) To compare fuel cell power to solar power, I needed to collect some data to give myself a baseline. I ask you the reader, please review and let me know if you feel I am missing things and/or doing something wrong. My new experiment was performed by putting a craft in LKO, 125km circular at 0 degree inclination. I drained almost all the power in the craft then opened one gigantic panel on the craft angled so it would be orthogonal to the sun. The period of the orbit was 2063.4s, and the net power gain during one rotation was 35,145 which gives an average output of 17.033 energy each second. But, being higher up allowed the craft to view the sun for longer than it really should have. Correcting for that amount, the average comes out to be 12.35 per second, or 24.7 during the day time. (I'll be using fractions of parts in these calculations since I'll assume our actual bases will really be much bigger. Also, I will measure efficiency by calculating the amount of liquid fuel generated when creating a fuel/oxidizer mix) Let's assume we are setting up a mining site at minimus and we luck out with 10% concentration right on the equator. From referencing the table, we need 4 drills to supply 1 IRSU. This draws a total of 90 power and weighs 7.25. If we supply this with fuel cell arrays, we need 5.05 of them for a total mass of 8.512. The fuel cells will draw 0.102 fuel per second, for a net of 0.348 fuel/second. Given this setup, the required mass to produce 1 fuel per second is 24.5 Now at this point I thought "Well, since this method consumes fuel, solar must give a better output" Assuming I calculated that average power per second correctly, we need 7.366 solar panels to supply the power. Minimus has a rotational period 40,400s, so we need a daily power output of 3,675,415. This requires 1,837,707 worth of battery storage to work through the night, or 459.43 of the 4k batteries. With all those batteries, our mass required to generate one fuel per second is a staggering 225, over 9 times less efficient than using fuel cells. If we removed the batteries and just relied on solar power for half the day then we get a much better rate of 25.63, since only half the daily energy production is needed if we are only running half the day. This does put us a bit above the efficiency of fuel cell arrays, as long as you can turn on your drills at the right time each day. Math equations (mostly taken from the wiki) http://wiki.kerbalspaceprogram.com/wiki/%27Drill-O-Matic%27_Mining_Excavator Drill output: 0.05 * concentration (between 0 and 1) * engineer skill Engineer skill: 5x for level 0, 9x for level 1, 13x for level 2, 17x at level 3, 21x at level 4 and 25x at level 5 ISRU output: 0.45 fuel per second when making fuel/oxidizer mix