Production Chains have always been an important part of the Anno series, and Anno 1800 is no different. The easiest way I can think of to describe it is that Production Chains dictate the relationship between the various resource you create. By combining them in different chains, using different buildings, you can create different resources to meet the Needs and Happiness requirements of the people who live in your city.
How Production Chains Work
Let’s take a look at a very simple early game Production Chain for a resource we will need a lot of, Timber. To create Timber, we need to start with the Lumberjack’s Hut, as it will produce Wood. The Wood can then be taken to the Sawmill, and the Sawmill will produce Timer. Each building will have a set maintenance cost and a set requirement for a type of worker. In the cast of the Sawmill, the maintenance cost is $10, and the worker requirement is ten farmers. As long as both of these are available, the Sawmill will worth at 100% efficiency to produce Timber.
Output Versus Input
As the various resource producing buildings feed resources to each other, it is important to keep in mind that sometimes different chains will share buildings. A good example of this is Soap and Sausages. Both of these need Pig Farms, but a Pig Farm can only output so many resources and support so many other buildings with that output.
For example, to make Sausages you need one Pig Farm, and the output from the Pig Farm will support one Slaughterhouse. To make Soap, you need 2 Pig Farms providing output for 2 Rendering Works, and they provide enough output for one Soap Factory.
So, if you have 2 Pig Farms for a Soap Factory, but build a Slaughterhouse, you will need to build a new Pig Farm to provide enough output to properly support it.
To find out exactly how much output it takes to support different types of buildings, I strongly advise you to check out the Anno 1800 Fan Wiki. Keeping the Output and Input of the various buildings balanced is vitally important to keeping all your citizens working at maximum efficiency.
Easily the most important thing to remember as your game progresses is always to ensure that you are building the right amount of steps in a Production Chain to support the steps that come after it, and be very mindful of the times that Production Chains share resources. If you have been getting lots of messages that a factory or business doesn’t have enough resources, then it is more than likely the case that those resources are being drained off by another Production Chain.