This doubles the amount of energy you get from mining stations. Which is *huge*. Before this I was fine on energy, but I didn't have enough to quickly get the thousands needed for terraforming many planets. So this relic really propelled my empire forward. One the one hand I know that some people want these impactful bonuses and I agree that some 5-10% modifier is boring, but I think 100% is a bit much. Even 30-50% would be very noticeable.