Ecosia vs Google

Performance

• Ecosia uses Bing and Yahoo.
• Google uses only their own engine.

Advertising

• By every click on an Ad on Ecosia, they take some of the money for saving areas of the rain forest.

Ecology

• Since Ecosia needs an additional server to display their welcome screen, it's likely that Ecosia needs more energy than Google alone (without Google Instant).
• Google spends some of their money to research of regenerative energy sources.

Speed and Energy

• The less time you need to find the required information, the less energy is spent for your research.
• Making required information available needs indexing and calculation time (which usually is hidden to the general user)