It's summer here in the Northern hemisphere, and evenings are perfect for grilling. But as you head out the back door with a plate of veggie burgers and kebabs, is it more sustainable to light up some charcoal, or use a propane tank?
As with most showdowns, this one's a bit fuzzy, but charcoal can come out ahead if you're willing take the effort to do it sustainably. But first, let's set a couple of things straight.
What you're eating matters a whole lot more than how you cook it.
The CO2 production in beef or pork far outstrips the CO2 you make cooking the food. So if you're looking to be more sustainable, the most important place to start is with what's on your grill.
Charcoal is not coal.
It's mostly compressed sawdust. About half the people we surveyed (myself included) were under the impression that charcoal was made from coal. Simply not true. Certain types of charcoal have coal and oil additives to help them burn, but in general, it's reasonable to think of charcoal as tightly packed wood.
So with those basics out of the way, where does that leave us? We'll, we've got two good ways to look at grilling's impact: energy usage and CO2 production. We'll get into the nitty-gritty in the Fine Print, but gas wins over charcoal quite handily in both categories. But didn't we just say that charcoal came out ahead? Yep. The answer, once again, taking a step back to look at the Life-Cycle Analysis for both.
The single biggest concern for both is the amount of CO2 they produce, and its effects on Climate Change. While charcoal releases more CO2 when burned, it's the same CO2 that was pulled out of the air when the trees and plants that made the charcoal were growing. Gas, on the other hand, usually comes from deep underground.
The net result is that charcoal keeps atmospheric CO2 constant over the long haul, while gas increases the amount of CO2 in the atmosphere, increasing Climate Change. But there's always more to the story. Let's check out the fine print.
CO2 cycle for charcoal.
CO2 cycle for propane.
The Fine Print
The most cited scientific analysis of charcoal vs. gas comes Tri stam West of Oak Ridge National Laboratories. Assuming a grilling time of one hour, and a heat of 35,000 btu per hour (fairly reasonable numbers for a large bbq), he found that gas released about 5.6 pounds of CO2, charcoal released 11 pounds, and electric came in last, releasing 15 pounds (this assumed an average US mix for electricity).
We must also look at the processes of making gas and charcoal. More efficient is better, since we don't end up throwing energy away that could have been used to do something. The best effiency information seems to come from a review that's largely based on a study by Eric Johnson. These two found that between the ground and your grill, propane only loses about 10% of it energy in transport, refining, bottling, and other losses. By contrast, charcoal lost 70-80% of its energy (mostly in burning wood to make heat to bake the charcoal) and needs some additional energy in creation - so the energy and CO2 numbers above are even more magnified with charcoal.
It's also important to note that even those numbers are tricky. Some, but not all, charcoal production plants use what's called co-generation. This means that waste heat from what's used to bake the charcoal is re-used to dry out briquettes, heat the building, and perform other tasks.
We also have to keep track of where, specifically, the charcoal or propane came from. The carbon-cycle case for charcoal only works if it's being produced from sustainabily managed forests. Plus, typical light-the-bag charcoal contains coal, oil, and lighter fluid, which when burned, create more than just CO2, and can be worse for the atmosphere than using propane. Unfortunately, it's not yet possible to obtain propane that was created from biomass, or dead plants. This sort of gas would also be long-term carbon neutral, and someday, an ideal choice.
Finally, there's the issue of control. While a gas grill can simply be turned off when it's done, charcoal has no such off switch. This means that to use it sustainably, you'd have to keep a close eye on getting the amount of charcoal right!
Either. This one depends on you.
The worst option you have is regular charcoal with coal and lighter fluid additives.
Better is a gas grill, used wisely, and with gas lit only under what you're cooking.
Best is to buy sustainably-created charcoal with no additives and tend your grill well, using the miniumum charcoal needed to cook your food.
This one's up to you, and what you think you'll be able to stick with for the long haul.
So toss on some veggie burgers, potatoes, kabobs, or stuffed peppers, and enjoy the summer!
For those interested, we've done a little digging to find sustainable charcoal companies. The costs are similar to regular charcoal, and the taste is reportedly much better. However, we don't have any contact or personal experience with these products, so your mileage may vary!
Green Link Charcoal
Wicked Good Charcoal
The Original Charcoal Company
That's this week's showdown! Toss us your comments below, and if you have ideas for a future showdown, let us know!
As an added bonus, here's Steven's Recipe for awesome BBQ Veggie Burgers that have even converted a few carnivores.
Veggie burgers of amazing
I use Amy's Texas Veggie Burgers. They've got just the right amount of spice and great texture, and work perfectly with the sauce.
Mix enough to coat the burgers, and for several bastings while cooking. Save some extra if you want it to drizzle on when you're done!
1 part dark brown sugar
1 part light olive oil
1 part Sriracha sauce
1 part soy sauce
Mix well with a whisk, until the oil is evenly distributed. It should be a deep red, and spicy/smoky to taste.
Then, once your grill is hot, dip frozen patties into the sauce, and place directly on the grill. You're not going to want to defrost first, since they cook quickly, and using frozen patties gives the sauce longer to soak in and improve the flavor. Grill until hot, adding cheese (pepperjack is particularly good), jalapeños, lettuce, and whatever else you like.
Sit back with friends, a cold drink, and enjoy!