How can I increase my economy?

You need to build structures that generate Economy like Spaceports, Economy Centers and Capital.

Other structures also gives you economy; Urban Structures, Orbital Base, Shipyards, Orbital Shipyards, Orbital Base, Metal Refineries, Robotic Factories, Nanite Factories, Android Factories and Biosphere Modification.

One important point about Spaceports. The economy it brings is accumulative. Level 1 gives you 1 econ, level 2 more 2 econ, level 3 will result in 6 econ in total and so on.

Free accounts spaceports are limited to the amount of bases the player have. So if you have 5 bases, you cannot build spaceports level 6.
Premium accounts have no limits to build it, but the accumulative economy holds when the structure level reaches the player amount of bases.

Check this table:

Level Econ boost
1 1
2 3
3 6
4 10
5 15
6 21
7 28
8 36
9 45
10 55

if you have 8 bases, the last two econ boost would remain as 36

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