As others have posted, what constitutes a subsidy is tricky. It's a word that's used in many different ways in different contexts.
Fact is, actual direct subsidies for fossil are quite low, they range in the billions. i.e. say the costs of oil businesses to produce and sell oil profitably is $100 per barrel, but they receive $10 from the government per barrel and sell at $90, that's a pre-tax or 'direct' subsidy. That's usually what we talk about when we talk about subsidies, a company receiving extra money, financial support.
This ranges in the hundreds of billions worldwide, which is a fraction of a percent of the world economy. Significant, yes, but not in the grander context.
Then there's post-tax subsidies, these range in the trillions. They're not actually money received by oil companies, and therefore it's misleading to the 'everyday man' to talk about subsidies because that's what the everyday man thinks about when he hears the word 'subsidy'.
What are these subsidies? Well say there's smog from cars that run on oil, and smog causes cancer and cancer causes healthcare costs and lost labor force due to death. Put a price on that, and you have a cost of oil that society has to pay for, that isn't priced into oil. You can price it in through tariffs and taxes and such, not doing so means oil companies generate costs onto society that they're not having to pay for. And if you add it all up, it's trillions of dollars, and that's when you get to the oft-cited 'subsidy figure' of $5 trillion from an IMF study. This isn't money these companies are receiving, it's money they're not being forced to pay up.
Now you can think what you want. I'm of the opinion these externalities should be priced in, and paid for by oil companies (and indirectly by the customers, who will change behaviour as fossil becomes more expensive, which changes investments geared towards renewable). Regardless, I don't think it makes sense to talk about a 'subsidy', unless you're having a chat with policy makers or economists. But in every day conversations with people, people don't use the word subsidy this way.
Either way, that's just a side note. The main point is this, it's obvious that fossil subsidies are substantial, but how big are they relatively to renewable? A fair way to compare is to look at the amount of subsidy per unit of energy. And they're gigantic for renewables.
For example:
http://www.forbes.com/sites/timworstall/2013/11/13/renewable...
Regardless of whether those numbers are exactly right, most studies confirm this disparity, hell if you follow the industry you'll find virtually all CEOs of all solar companies talk openly about this. e.g. the SolarCity CEO has a couple of entrepreneurship videos on youtube speaking to uni students about this. And that's fine, understandable and acceptable. It's obvious the world won't sustain itself without renewables, it's also obvious we have to hit some harsh deadlines, and that we couldn't let the market create the financial incentives by itself to get the hundreds of billions of investments necessary to get a renewable industry running that has a chance of success. I support the ridiculously high subsidies, it's the only way we'll get there.