SodaStream carbonator: Seltzers on tap

Are you a sparkling-water person? Then you should know about SodaStream, a countertop gadget that carbonates water quickly and easily. While other home-based carbonators can be unwieldy or downright dangerous, this device is incredibly easy to use and requires no power. It's got a big green angle, too — potentially eliminating all those cans and bottles you use for soda. Even if you recycle them, that's a lot of energy and effort wasted on transport.

After living with the SodaStream "Penguin" for the past few weeks, I've stopped buying seltzer (my fiancée is a fanatic). And, to my surprise, I actually prefer what comes out of the SodaStream to anything store-bought. The full 411 on the SodaStream — along with an important caveat — after the jump.

Setting up the SodaStream is easy — the most challenging part is inserting the CO2 tank — and using it is even easier: Fill half-liter carafe (2 are provided in the starter kit) with water, place in Penguin, push lever down, release pressure, done. Now you've got sparkling water that rivals Schweppes.

It makes sense that the sparkling water that comes out of the SodaStream is better than stuff from the grocery store. The Penguin gives you direct control over the carbonation of your beverage. Like your soda to really pop? Push the lever down a few more times. Want it just slightly fizzy? Once will do.

If you like what comes out of the SodaStream, the next question is, "How much does it really save me?" The Penguin starter kit costs $200. Once you have it, the only thing you need more of is CO2, so you'll need to send back the tanks and get shipped new ones, at a cost of $13 each plus shipping.

Each tank is said to carbonate 60 liters of water. Assuming a consumption rate of about two liters of carbonated water per week, you'll typically go through about two tanks a year. So assuming SodaStream lasts you, say, five years, it comes out to about $1.30 for sparkling water per week (not counting the cost of water from the tap).

The Big Caveat: The instructions explicitly say that you should carbonate only water in the SodaStream. This throws a wrench in the works of anyone planning to re-carbonate flat Pepsi or Budweiser. If you want flavored beverages, you'll have to turn (naturally) to SodaStream's flavor additives, which come in bottles that sell for five bucks each and can flavor 12 liters of water (sample packs are available, too). The justification for this — that other beverages might clog the nozzle — sounds a little weak, though doing so will definitely void the warranty. After sampling a few of SodaStream flavors, I think they taste about as good as any generic stuff, but Coke it's not.

That could be a deal-breaker for some, but in my household, where we used to spend somewhere between $5 and $10 a week on sparkling water, we're sold. In a greater sense, SodaStream represents the best of green innovations: It saves you money, reduces your environmental impact (no more cans or bottles), and doesn't require that you give something up.