The US Senate is considering an “Albedo Modification Geoengineering Proposal”.
Budgetmakers in the U.S. Senate want the Department of Energy (DOE) to study the possibility of making Earth reflect more sunlight into space to fight global warming. Earth’s reflectivity is known as its albedo, and the request to study “albedo modification” comes in the details of a proposed spending bill passed by the Senate appropriations committee to fund DOE, the Army Corps of Engineers, and related agencies for fiscal year 2017, which begins 1 October. The bill does not specify how much money should be spent on the research.
In a surprise move, 200 companies in China decided to bid on the contract. Most of their plans involved reopening all the coal power plants President Obama has shut down.
sunshine hours 
I wonder if they’re going to develop projectiles shot into the upper stratosphere (20-30 miles) that would expel SO4 and parachute back down to the surface. They’ve already done proof of concept projectiles that get 122 miles high using an ultra-long and ultra-powerful cannon; this wouldn’t need to be nearly as strong and could lift a bigger payload. Since the sulfates would reflect more of the incoming solar radiation, it would more than offset the minuscule CO2 produced from the gunpowder charges.
Of course, a person could just wait a few years for the weakening sun to do it all for them … but why deprive the DoE and DoD of their pet projects?
This paper suggests 747’s (or maybe something with a higher altitude capability. 1,000,000 tonnes of sulphuric acid a year.
Click to access erl427423suppdata.pdf