While quantitative estimates vary, the investments needed for transition are certainly huge; they need to be sustained for a long time. Governments have a central role in that they need to point the way by adopting an appropriate policy framework. A clear and credible path for government regulatory and fiscal action is also a prerequisite for efficient choices on the part of private finance.
Indeed, while many governments will directly invest their own money in many countries and MDBs will play their part, it is likely that the private sector will be called upon to finance most transition investment. There will be no transition without a general awareness of the need for it and a willingness, even a desire, to finance it.