This morning the New York Times published what they are calling the most detailed map of auto emissions in America. In it, they remind us that transportation is the largest source of greenhouse gases in the US today and that most of it comes from our driving habits within metro areas. See below charts.

Not surprisingly, if you look at total on-road emissions, the biggest cities -- New York and Los Angeles -- are at the top of the list. But you also have car-dependant regions like Dallas-Fort Worth that punch above their (population) weight in terms of total emissions.

Now, here's where it gets interesting. The story flips as soon as you adjust for population.

On a per capita basis, New York is pretty much at the bottom of the list. It is yet another reminder that one of the most sustainable ways to live is in a dense urban environment where it is possible to get around without the use of a car. New York is, of course, one of the best places in the US to do exactly that.

Charts: New York Times

Phoenix is the 5th largest city in the United States. It has a city proper population of about 1.6 million people and a metro area population of close to 5 million. It is also one of the fastest growing cities in the US.

But being the desert city that it is, its population consumes more water than its natural aquifers can support. Which is why there is something called the Central Arizona Project (CAP).

Approved in 1968, the CAP diverts water from the Colorado River into the state of Arizona. The system is 336 miles (or 541 km) and it runs from Lake Havasu to Tucson, via Phoenix.

Here is an aerial image of the canal from Wikipedia Commons:

And here is a system map from CAP:

Today, it is the single largest water source (and consumer of power) in Arizona, serving about 80% of the state's population. This obviously makes it invaluable. It delivers on average about 1.5 million acre-feet of water per year. (Acre-foot = Acre of area x one foot in depth.)

I was reading about this project today and I found it fascinating. Maybe some of you will too.

Snøhetta has just completed an office building in Trondheim that produces more than double the amount of electricity that it consumes. If you recall my recent post on Norway's new coastal highway, you may remember that Trondheim is the northern terminus of highway E39. I mention this because of access to sun. Latitude 63.43.

The office building is about 18,000 square meters and it is wrapped with about 3,000 square meters of solar panels. The roof is angled at 19 degrees in order to maximize sun harvesting, and any excess electricity is fed back into the city's grid / neighboring facilities. Large batteries also help to help carry the building through the winter months (again, latitude 63.43).

Here are a few photos of the roof (via Dezeen):

I wish I had more of the details so that I could see how the numbers pencil. Hard costs, utility costs, office rents, government incentives/disincentives, embodied energy in the batteries, and so on. Because this looks like an extraordinary accomplishment for a city that is remarkably north.

Images: Dezeen