
I want to talk about scale and size in our urban infrastructure, but it will take me a few minutes. Stick with me.
I started off last week continuing to think about the grid, or grids, that make cities work. Kind of.
Actually, our cities don’t really work very well at all, and their grids are pretty much a total disaster. One of the biggest challenges we face in constructing the next city is in retooling our broken, outmoded, under-maintained, obsolete, inadequate infrastructure – our grids.
Here in Washington, as in most US cities, we have: water problems, when the Potomac is often drained of as much as 85% of its flow during hot, dry summer days; extreme sewage problems, with 2 to 3 billion gallons of raw sewage dumped annually into the Anacostia River during major rain events; power problems, best understood when our electricity supplier, Pepco, declares their pathetic goal of hoping to produce 20% or our energy using renewable sources by 2020; and communications problems, because we have no fiber optics and very spotty wi-fi, mostly limited to the Public Library branches and local coffee shops (We had better wi-fi in the middle of an Egyptian desert than we have here at home).
Oh, and our vehicular grids don’t work either, though as non-car people we notice this less than most of our neighbors. And we don’t care much if all the cars can’t move – get rid of them. But it is true that DC has some of the worst traffic and congestion in the country.

As I thought about these grids and all their problems, I found myself wondering what it would take to get free of this mess. And how much it would cost.
Intuitively, I suspected that getting totally off the grids at the scale of our one Capitol Hill rowhouse here in Washington would be a difficult and expensive proposition. We certainly could mount a solar array on the roof for some of our power and/or hot water, convert to geothermal by drilling holes in the backyard, install composting toilets. But getting all the way off the grids? Probably not very achievable in our relatively dense urban setting.
So what about a scale shift in my thinking? What about trying to do this at the scale of our block – 57 rowhouses with an alley that is so narrow virtually no one can use it. Take a look:

If we used the alley space communally, we could install distributed combined heating and power (CHP), a kind of district CHP system like those used on campuses and in similar places, perhaps fueled by renewable biomass of various kinds. We could close the water loop, treat the gray water or use it in irrigation and sanitation, capture the sewage for compost, and maybe to augment the district CHP, build a solar array at a scale that would be useful and install a wind turbine or two. Now we’re making some headway.
As I did research into the technologies, systems and equipment, costs, and looked at problems or obstacles, I was really struck by something interesting: there is not a lot of discussion of problem-solving at the scale of a city block. The individual house, usually out in the country, yes – or at the scale of the nation. But not much about the block. There is a group called “One Block Off the Grid,” but it’s just about solar power, not about the larger issue of all the grids that are a mess.
Most of the discussion I encountered has to do with solving the grid problem, or grids problems, at a national scale. The costs are staggering, the time needed to transition way too long – we’ll all be swimming, in the dark, by the time any progress is made – and there are all kinds of fairly virulent arguments about how to proceed.
Just one example will illustrate. Some scientists propose that we transition from a carbon to a hydrogen economy. They propose replacing the national electrical grid with a super cooled hydrogen grid. By 2050. Other scientists say this is crazy, dangerous, dirty, infeasible, requires scores of nuclear reactors. Costs are in the trillions (the American Society of Civil Engineers says it will cost $1.5 trillion just to fix the grid we already have). I hear fiddle music and Rome is burning.
So what can we afford, what is feasible, what can we implement fast? Even thinking at the scale of our city is problematic. To fix the problem of sewage dumping in the Anacostia here will cost over $2 billion. That stops sewage going into the river, but it really doesn’t fix the sewage problem, use the sewage in any way, or close the wide open water loop. A desperately needed patch, but a patch nonetheless.
Coupled with an absence of local, city-block based thinking is another flaw in thinking: lots of talk about what constitutes THE solution, when in fact we will need all possible solutions. There is no one solution to any of this mess.
At the scale of our block, we can employ all the tools in the tool bag. District CHP, mini-CHPs per house, solar, wind, geothermal, distributed water treatment and management, waste handling and reuse.
Through a nearly endless number of visits to incredibly arcane websites, I think I have a ballpark order of magnitude estimate of what this might cost us and our 56 neighbors. I am going to guess that we can get pretty close to off the grids for something in the vicinity of $2 million or $3 million. This works out to between $35,000 and $50,000 per rowhouse.
I know, I know, you will pick me apart on all the details. That is where where the devil lives, after all. As far as I can tell, there are no models or templates to examine for answers. Some new construction, yes, like the Bedzed housing development in England (100 units, district CHP using biomass, zero-energy). But I can’t find anybody that has retrofitted a city block to get it off the grid.

BedZed, in London.
The technology is now present to do this. We will have to do a bunch of tinkering to find the right combination of tools to solve the problem. But if I can wrangle up a couple of million bucks, and convince my neighbors to give it a shot, perhaps we could at least get started trying.
And, in the long run, we wouldn’t need the national grids for much any more. So the scale problem of national infrastructure and trillions of dollars gets solved by being as local as possible – the city block.
In a time of 3,000 pound personal transportation devices, and access to the globe at any moment from our easy chair, it is hard to focus on the right scale of endeavour to make progress in shaping the next city. But I am going to stick with my intuition on this one – start thinking about city blocks. Not cities, not regions, not states, not the nation. Just stick with the humble city block.
Oh, and one last thing. Amy asked me if I could calculate the time it would take to pay back the $35,000 to $50,000 investment in savings from utility bills. My reaction: very, very soon, payback time will be irrelevent. Sorry folks, but if the lights don’t go on anymore, or if you have no water when you turn on the faucet, payback doesn’t mean much at all. And that’s where we’re headed, real soon.
Talk amongst yourselves.
Read Full Post »