This one for instance (~$13k) that argues it will save money:
http://www.wsj.com/articles/a-guaranteed-income-for-every-am...
Its pretty clear the entire savings comes from cuts to Medicaid & Medicare & Agricultural subsidies.
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> 3. Propose a low (subsidence-level) basic income, which represents a major cut in benefits to pensioners and the disabled. Since those two groups receive the bulk of current welfare spending, redirecting their benefits is the only means by which a UBI can be feasible.
That one one went with a clear option #3.
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As for your solution, it works-ish, but ultimately requires maintaining Medicare & Medicaid which inflates the cost beyond what you propose or admitting you are doing #3 also.
So you'd need to actually raise ~$5.8 trillion to make your system work. It can work, you'd just need to basically double the current tax levels.
For example 320 million Americans * 15K/year in basic income = 4.8 trillion dollars that has to come from new taxes and spending cuts.
But if it all comes from tax increases than somebody currently making the average income will see their taxes go up by exactly amount as their BI payment. Is that actually a tax increase? And if we can get cost savings from simplifying welfare, then their BI payment is more than their tax increase.
4.8 Trillion is completely unfeasible, but the real cost is in the order of hundreds of billions. A heck of lot, but it is feasible.