The tractable general equilibrium model developed by Golosov et al. (2014), GHKT for short, is modified to allow for stock-dependent fossil fuel extraction costs and partial exhaustion of fossil fuel reserves, a negative impact of global warming on growth, mean reversion in climate damages,...

Climate change must deal with two market failures: global warming and learning by doing in renewable use. The first-best policy consists of an aggressive renewables subsidy in the near term and a gradually rising and falling carbon tax. Given that global carbon taxes remain elusive, policy...

The Green Paradox states that, in the absence of a tax on CO2 emissions, subsidizing a renewable backstop such as solar or wind energy brings forward the date at which fossil fuels become exhausted and consequently global warming is aggravated. We shed light on this issue by solving a model of...

Our main message is that it is optimal to use less coal and more oil once one takes account of coal being a backstop which emits much more CO2 than oil. The way of achieving this is to have a steeply rising carbon tax during the initial oil-only phase, a less-steeply rising carbon tax during the...