Measuring the temporal dynamics of policy mixes – An empirical analysis of renewable energy policy mixes’ balance and design features in nine countries

•First attempt to analyze the evolution of policy mixes in a larger-n study.•Propose ‘balance’ as a new policy mix characteristic.•Conceptualize policy mix design features, linking policy design and mix literatures.•Countries’ policy mix dynamics vary strongly regarding some variables.•Discuss implications of our findings for future policy mix research.