I want to assess the effects of energy saving technologies on output growth using time series data. My work would benefit from time series data on patents for energy saving innovations, but this is hard to find. I have time series data on energy service prices (not energy prices), which I am thinking of using as a proxy for energy saving technologies. Energy service prices appear to have declined over time and this is due to the improvement in energy technologies, mainly. Thus, I assume the energy service price data reflects the improvements in energy technologies.
Do you think the idea of proxying energy technologies with energy service prices is appropriate in an empirical analysis?
Edit: Price of energy refers to the price of energy carrier, say oil. Energy service price refers to the cost of providing an energy service, say heating or lighting etc.