For the latest data on the world’s energy markets, organizations such as the IEA (International Energy Agency) and the EIA (Energy Information Administration) are crucial sources.
Every year, investors and entire industries rely on their reporting on energy supply and demand, as well as their forecasts going forward.
However, these organizations tend to be better at some things than others. For example, in terms of summing up past and current data on what is going on in the world, they generally do a pretty good job.
In other situations, such as trying to extrapolate numbers on current trends or predicting the tipping point of technologies, things get a bit dicier. Forecasting the roll-out of solar, in particular, has proved to be a daunting challenge for these organizations over the years
Source: http://www.visualcapitalist.com/experts-bad-forecasting-solar/