We began investing in renewable power and made increasing use of natural gas through market power purchases and the acquisition of a gas-fired power plant in New Mexico. But coal still provided the lion’s share of the energy Tucson residents used during this period.
To reduce the environmental impact of our coal fleet, we spent hundreds of millions of dollars to install modern pollution control equipment. These investments cut nitrogen dioxide emissions in half and reduced sulfur dioxide emissions by more than 70%.
You should know that these charts are based on TEP's 2014 Integrated Resource Plan, which treats energy efficiency (EE) like any other energy resource. For that reason, they include both the energy TEP delivers and the energy we won't have to produce thanks to our EE programs. That's why the percentages shown for other resources — like renewable energy — are smaller than their share of our actual energy mix. So rest assured that TEP is on track to meet or exceed Arizona's Renewable Energy Standard, even if the percentages shown here appear to lag behind those annual goals.