New York. NY —
Despite the alarming and deadly steam pipe explosion on 41st street this week, most of Manhattan south of 96th street continues to get its heat and hot water thanks to steam. A hundred and five miles of steam pipes are buried several feet below the streets in what remains the world’s largest steam network. As WNYC’s Beth Fertig reports, the century-old system is still considered highly effective.
REPORTER: The professionals who deal with steam can usually spot a leak by the hiss.
MOSTO: What we have here is this is a valve coming off of the main feed in the steam room.
REPORTER: Steve Mosto is an engineering consultant who helps office buildings manage their steam operations. We’re in the steam room of 825 Third Avenue and it’s hot in here. Thick yellow pipes carry 375 degree steam heat direct from Con Edison’s underground network to the 43 floors above. The steam provides the building with its heat. In this case, it also provides pressure for its air conditioning units. The whole system is controlled through valves and meters.
MOSTO: At various times, a joint can be there for years and then you have a leak like we have here, so tonight we’re going to shut it down, they’re going to loosen the joint, put in a new gasket and then tie it up together and the leak will be stopped.
REPORTER: With 180 pounds per square inch of steam pressure, Mosto says leaks happen on a regular basis in every building – which is why steam rooms are constantly being managed. The real threat is condensation: excess water building up in the pipes.
MOSTO: The main concern we have for safety is that we remove condensate we do not let that inside the steam system allow that build up.
REPORTER: Or what would happen? Then you could have a water hammer type of condition in which water builds up inside the steam system, and it builds up to such an amount that it fills the pipe and it’s sent down the pipe with a very strong force and that’s what can damage the pipe and create – it can create something like what we saw earlier this week.
REPORTER: Con Edison hasn’t determined the cause of this week’s blast. But that is one of the theories. New Yorkers have also wondered if age is a culprit. The pipe that burst was built in 1924. But even though New York is still using system designed in the late 19th century, it’s managed with 21st century technology.
TRIMBOLI: What happened on 41st Street is something which happens in the street which we have no control over. In a commercial office building there are many, many checks and balances in place.
REPORTER: Lou Trimboli is the Real Estate manager for CB Richard Ellis, which manages 825 Third Avenue. In his office, he is using web-based technology Steve Mosto works with to monitor the building’s steam system. With that, they can track any potential problems AND know exactly how much steam they’re using at any time.
TRIMBOLI: By buildings becoming more efficient, they’re going to make Con Edison more efficient. So now we are looking at steam say vein as we are looking at electric and say, if I can start my steam-driven equipment at 4 o’clock in morning instead of doing it at 7 or 8 when 2,000 other buildings are doing it, I may run a more efficient building that way.
REPORTER: Starting this fall, Con Ed will be charging steam customers more during peak hours. State regulators have urged the company to become more cost-efficient. Con Ed is the only supplier of steam in Manhattan and it’s a small business compared to gas and electric, generating just 7% of its annual revenues. Ashok Gupta heads the air and energy program for the Natural Resources Defense Council.
GUPTA: The question is really how Con Ed goes forward to make the investment it needs to make for producing steam then delivering it in a safe and reliable way.
REPORTER: Con Ed says it already spends $30 million a year maintaining its steam system. But Gupta says it could do more to make its steam producing power plants more efficient because they run on fossil fuels. And with heightened concerns about the city’s aging infrastructure, virtually no one would argue against a greater investment in maintenance. The last major steam pipe explosion in 1989 killed 3 people. Con Ed has also gotten several violations in each of the past few years for not responding to emergency calls in a timely basis, and for inspecting equipment a few days later than planned.
REPORTER: But despite this week’s tragedy, Steve Mosto says steam is still considered efficient and necessary for this energy hungry city.
MOSTO: There is too much of the city and too many buildings that are dependent on steam as a source for heat and as for cooling energy that it’s impractical for them to install alternate sources, and to have electricity to run their heating system or to run their cooling system, thousands of megawatts are off loaded from the electric grid here in NYC and handled by steam chillers and that program was started years and years ago in anticipation of the grid being maxed out.
REPORTER: That’s why he says with the right amount of maintenance and efficiency, steam could be the next form of green. For WNYC I’m Beth Fertig.