Google Inc has abandoned an ambitious project to make renewable energy cheaper than coal, the latest target of Chief Executive Larry Page's moves to focus the Internet giant on fewer efforts.

Google said on Tuesday that it was pulling the plug on seven projects, including Renewable Energy Cheaper than Coal as well as a Wikipedia-like online encyclopedia service known as Knol.

The plans, which Google announced on its corporate blog, represent the third so-called "spring cleaning" announcement that Google has made since Google co-founder Page took the reins in April.

The changes come as Google is facing stiff competition in mobile computing and social networking from Apple Inc and Facebook, and as some investors have groused about rising spending at the world's No.1 Internet search company.

"To recap, we're in the process of shutting down a number of products which haven't had the impact we'd hoped for, integrating others as features into our broader product efforts, and ending several which have shown us a different path forward," wrote Google Senior Vice President of Operations Urs Holzle in the blog post.