The problem is that "once we have CO2-neutral energy production" is way too late. There are several tipping points where the rising temperature sets off other processes that speed up warming even further.

For example, when the Russian permafrost melts, it will release gigantic amounts of methane, a very potent greenhouse gas, into the atmosphere. Once that happens, not only do you have to capture all the CO2 you emitted, you also have to capture all that methane.

Also, you'll want to recreate the kilometers-thick ice sheets in the arctic. When those are gone, the earth's albedo will drop, which means that it heats up even more quickly since less sunlight is reflected.