Perhaps the only kind of barbecue that won’t irk Mother Earth is a solar grill. But you won’t find one at the nearest hardware store; only a few websites sell the solar cookers. There’s no smoke, but there are mirrors, which focus the sun’s rays on the grill tray.

None of the familiar fuel sources are as noble as the sun. Gas, electricity, wood, and charcoal each have downsides, but gas puts out the least carbon dioxide.

The charcoal-wood crowd can cut the toll. Fans of wood’s smoky flavor might consider a hybrid grill, powered by gas with a small area to burn fragrant wood chips. Charcoalists can seek brands that don’t add undesirable ingredients like coal dust, sodium nitrate, and borax. And instead of a squirt of lighter fluid, which emits volatile chemicals, try an old-school chimney starter: a metal cylinder with a small compartment at the bottom for paper. Light the paper and the coals above come to a hot glow.

The price tag matters. A cheap, short-lived grill has a more damaging eco-footprint than a durable solid metal model. Stainless steel and porcelain-enameled cast iron not only outlast but also cook more efficiently than chrome-plated aluminum. Besides, chrome is prone to corrosion. And that definitely doesn’t go well with ribs.

Gas

Both natural gas and propane are efficient to produce, and natural gas is the cleanest burning fossil fuel. But they are nonrenewable resources and give off some pollutants.

Electricity

Unless sun or wind is involved, it’s not as efficient to produce as gas. But electric grills burn cleanly.

Wood

Trees are felled. Ash and smoke are exuded. But wood is a renewable resource.

Charcoal

Most is made from leftovers: scrap wood and sawdust. But charcoal’s manufacture creates greenhouse gases.