19 August 2009

State Park of the week: C. R. Magney

The next state park takes us far up the North Shore, through Two Harbors, Lutsen and Grand Marais to Judge CR Magney State Park. Judge Magney was the mayor of Duluth in the late 1910s and, later in life, an associate justice of the Minnesota Supreme Court. He was also a driving force in the establishment of many of the parks along the North Shore and his favorite, along the Brule River, was named for him.

The Park has any facilities and sights to see. It is almost a recent archaeological dig, with the foundations for a WPA camp from the 1930s interspersed amongst the campground. There is lakeshore along Superior (with wonderful pebble beaches all the way down to Grand Marais) and a beautiful section of the Superior Hiking Trail. The most famous sight in the park is, however, Devil's Kettle Falls.

The Brule, like many rivers of the North Shore, is rather placid until it tumbles over a basalt (I think) formation on its way down to the lake. However, while most rivers go over a falls and then proceed onwards, the Brule shakes it up a bit. The river splits in two over the falls. The eastern half falls on to a ledge, splashes, and goes on its merry way. The western half falls in to a deep, dark, foreboding pothole and seems to disappears. No one knows exactly where it goes, although it probably courses through groundwater cracks back in to the Brule or in to Superior a couple miles downstream. Still, it is quite something to stand at the top of the falls and watch half a river disappear.

On a warm day, of course, you can swim in the river. Not in the Devil's Kettle, but downstream below "Upper Falls" (which is, paradoxically, the lower of the two main falls). You do have to hike in a mile, which takes you up a steep hill on bluffs overlooking the falls and then down a staircase to the swimming hole. (Devil's Kettle is up another pitch, but well worth the trip.) This discourages some visitors, but its still a popular place. For solitude, however, you can walk north along the Brule River, where the Superior Hiking Trail becomes much narrower and less-used. Or, spot a car at the northern end of the park and hike downhill—you can leave a bike at the bottom to get back.

Devil's Kettle isn't particularly close to the Twin Cities—plan on 5 hours if you don't hit any traffic—but it is one of the more unique spots in the state and well worth a visit.

12 August 2009

170? 230? What do all these numbers mean?

You may have seen the recent headlines:

Dakota County students say hybrid gets 170 mpg
G.M. Puts Electric Car’s City Mileage in Triple Digits

Everyone is excited about high-mileage plug-in hybrids (GM has run a long, mysterious advertising campaign touting the 230 mpg figure). That's all well and good, but, really, is there a good way to measure energy use in miles per gallon when a fair amount of the energy in these cars is measured in miles but not in gallons? HOURCAR's own plug-in hybrids (oh, yes, we're way ahead of the curve; we got our first back in '06) are advertised as 100+ mpg and, under the right circumstances, achieve that. Sometimes. So, should we take all these new numbers with a grain of salt?


As this page has discussed before, mileage estimates are just that: estimates. They are very variable. And the higher the mileage, the more variability will occur. Especially since the EPA has not yet finalized how they are going to measure PHEVs. GM's own Volt site has the disclaimer that
230 MPG and 25 kWh per 100 miles driven represents a preliminary GM est. of the final approved city rating; actual MPG and electricity consumption will vary based on many factors including driving habits, weather and road conditions and operation of electrical systems in the vehicle.
That's a pretty big group of ifs! It depends on the final rating, the actual consumption and many additional factors. Maybe 230 is a best-case scenario. Maybe not. But there's really no way to know.

The news articles, when you read past the lede, are not much more forgiving. The Times says:
The rating number, based on methodology drafted by the Environmental Protection Agency, is somewhat abstract, one auto specialist said, given that much of the city driving of electric vehicles will rely solely on the battery charge.

Figures for highway driving and combined city and highway use have not been completed for the Volt, but G.M.’s chief executive, Fritz Henderson, told reporters and analysts at a briefing on Tuesday that the car was expected to get more than 100 miles a gallon in combined city and highway driving.
100 mpg is slightly less than 230, and these numbers are coming from the same folks who, a few short years ago, thought the Hummer was the future of American motoring.

CNN goes to point out that this number has not been vetted:
The Environmental Protection Agency … says it has not tested a Chevy Volt and therefore cannot confirm the fuel economy values claimed by GM.
It goes on to point out that
Fuel economy for hybrid vehicles like the Toyota Prius is displayed in the same way as it is for any other gasoline-powered vehicle. It gets 46 mpg, for example, versus 19 mpg for a V-6 Ford Mustang.

That standard works because all the energy used by the Prius ultimately comes from burning gasoline. The Prius just uses that energy more efficiently than other cars do. The Chevrolet Volt, on other hand, runs on electricity that comes from two sources -- a battery as well as a gasoline engine.

When gasoline is providing the power, the Volt might get as much as 50 mpg. But that mpg figure would not take into account that the car has already gone 40 miles with no gas at all. So let's say the car is driven 50 miles in a day. For the first 40 miles, no gas is used and during the last 10 miles, 0.2 gallons are used. That's the equivalent of 250 miles per gallon. But, if the driver continues on to 80 miles, total fuel economy would drop to about 100 mpg. And if the driver goes 300 miles, the fuel economy would be just 62.5 mpg.
And there is, of course, the question of where all that electricity comes from. If it's from wind and solar, huzzah, it's clean. If it's from coal, as much of our energy is, it's not so clear-cut. Plus, how will a Volt measure up against the upcoming all-electric Nissan Leaf and rumored Prius Hybrid from Toyota? And how do you measure the efficiency—and pollution—put out by an all-electric vehicle?

Dave Friedman, quoted in the San Francisco Chronicle, may sum it up best saying that
Your mileage may vary means more to the owner of a plug-in than any other car on the market.
He also points out that conventional hybrids, paired with better engines and transmissions, will have more of an effect in the short term.

So, what does all of this mean? Well, there are couple of takeaways. The first is that while the future is closer, it certainly isn't here, and any numbers you see you should treat with a healthy level of skepticism (as well as a similar level of excitement). The second is that as we increase overall efficiency, how you drive will have more and more of an effect on efficiency.

Finally, as always, the best way to reduce your carbon footprint is to drive less. The marginal increase in emissions by taking the bus or train is almost zero, since they are running anyway. The marginal increase in emissions of walking or biking is negligible. In other words, it's great if your car gets 100 mpg, but your bike does a heck of a lot better than that.

11 August 2009

State Park of the week: Afton

We've been a bit remiss bringing your highlights of the state parks. Afton is close, its terrain is varied and scenery quite nice. As you drive through the gates (no need to stop with a daily rate HOURCAR) and down the road, you go from farmland to prairie to deep, green forest, and then back up to prairie. From the parking lot, there are miles of trails for hiking, running, and cross country skiing (and horseback riding, but I don't think you can carry a horse in an HOURCAR).

The main trail goes down to the beach on the Saint Croix. It's nice for swimming, and the water is temperate, although it is a bit choppy with lots of boat traffic on the river. There are buoys which keep the boats out of the swimming area (and yes, if you want to reenact the lyrics of a song which we can't print here, we do climb buoys instead of trees), though, so it's perfectly safe. The trails further along the river see fewer users, and while solitude can't be found on a summer weekend, a quiet walk through the woods is definitely in the cards. Up above the swimming area are a few dozen hike-in campsites, some in the woods and some up on the prairie. A word to the wise about these: they're all uphill, both ways.

Come fall, the colors will come to Afton, and in the winter, if the snow flies, the trails will be groomed (although they generally need a bit of snow to open). And the best part is that the park is only half an hour from Saint Paul, so it's an easy day trip (daily-rate HOURCARs can, of course, be rented by the hour) if you just have a couple hours to spend and want to get away from the rush. And, yes, you could bike there, too, although it'd be a bit of a haul; after 25 miles each way on a bike, all you might want to do is take a dip in the river.