Bitcoins can be acquired by 'mining' them, where a computer generates codes and if they're valid you going that bitcoin. Is this equivalent to Rica/interest?
Is it haram from some other means?
I don't believe I've ever read of any scholars discuss it, let alone issue any fatwas. So this will be personal conjecture.
But first, let's explore the definition of riba in Islam. There are some differences of opinion, but generally it is defined as "unjustified increase of value for one party during the exchange of commodities of the same type with the other party". So if I give you 30 grams of gold and you give it back as 35 grams then that is riba. Here is a very good article on the Islamic definition of riba.
Now let's look at BitCoin mining. I won't pretend that I understand it completely but here's a brief description: BitCoin is based on distributed book keeping among disparate computer systems to keep records and avoid double spending of the currency. This is called a block chain. If you offer your own computer system to be part of this chain (a very intensive computational task) you get rewarded with BitCoin. This is what is commonly known as BitCoin mining.
In essence you are exchanging your computer resources (hardware, time, electricity ... etc) in exchange for BitCoin. These are two different commodities, so there's no riba here.