What will drive growth beyond 2021?

We know that the economy grew by 1.2% in the second quarter. Economists have divergent forecasts for the full year's growth rate. Johan Els of Old Mutual predicts 5.5% growth for 2021, in July the Reserve Bank still said 4.2% and Investec estimates it could be 3.9%. Prof Raymond Parsons makes the point that we really should not worry about growth this year. The Covid-19 pandemic was a demand- and supply-side shock to the economy and even just a partial return to normal will yield a solid growth rate. The problem lies with 2022's growth. Where will the growth come from?