The Energy Matrix is the EI's online vault for energy information containing more than 90,000 resources that can be accessed online or in the EI library. Browse the Energy Matrix by clicking on a category to see the material we hold on this topic. Topics have been divided horizontally by theme, and vertically by stage in the energy value chain. In some cases, we have identified sub-categories, which help you to narrow a topic even further. Sub-categories will appear as you hover your mouse over the Energy Matrix. You can also use the Search box and Advanced Search function at the top of the page.