Residential Demand Metering - Commonplace or Not?

Our property currently has a 15Kva pole transformer feeding a 100 Amp service. In years past this same transformer was also used to feed a barn and a mobile home (all long demolished).

Given the history of this property (ie. an old farmhouse that predates the 1936 Rural Electrification Act, a couple of Fanny Mae foreclosures, and at least one Sheriffs Repossession) I don’t know exactly how much of the electrical (or any other) system is ‘legal/approved’ in this property, and I don’t want to arouse any undue interest in the ‘status quo’ by the PoCo, or any other regulatory agency, by prematurely asking any questions. Sleeping dogs, etc.

And while I haven’t yet caused any neighborhood ‘light flickering or low voltage complaints’ (but give me time!) with my 30 HP RPC, I certainly am over-taxing that 15Kva transformer from time to time (but for only short bursts with plenty of lower demand time in between).

However, 100 Amps just doesn’t hack it when EVERY local Realtor that we have approached regarding resale modernizations tells us that local buyers are increasingly demanding electric heat & AC (and passing on properties with oil or propane). Can they all be wrong about this buyer mindset?

So a 200 Amp service would appear to be a prerequisite regarding marketing this house in say 5 years time.

Then there is my workshop (which is needed to modify various pieces of excavating type equipment to better cope with working on the many slopes and gullies on this pre Civil War farmstead).

So there’s a 200 Amp supply for the workshop as well.

And since there are many 5000 sq ft ‘McMansions’ in the local area that have 2 x 200 Amp residential electrical services, I’m not concerned about our request for a service upgrade being denied outright.

However, how concerned should I be regarding the PoCo insisting on ‘demand metering’?

In this thread:

http://www.practicalmachinist.com/v...ers-vfd/right-15-transformer-20hp-rpc-226630/

Froneck commented (in posting #11):

"Also be careful what you wish for when talking to the power company! If you want larger service they might put in a demand meter while boosting your amperage! What ever you do Do Not mention high amperage for short durations as needed while starting your 20 Hp RPC!!! You'll get a Demand Meter!!!"

And yet in this thread:

http://www.practicalmachinist.com/v...limiting-rush-amperage-motor-start-up-226948/

Jraef commented (in posting #13):

"Despite COUNTLESS anecdotes about avoiding "peak demand charges", the reality is that you are NOT charged for motor inrush currents in 99.999999% of locations.... If you have a residential service, they don't have any requirements, but your service capacity may be the limitation anyway."

Froneck (in a subsequent posting) gave me two examples of residential settings that he knows of where demand metering was required by the PoCo. So, at least sometimes, it does appear that residential users are required to have demand metering.

Now, two examples doesn't necessarily make demand metering a foregone conclusion, but is this a likely outcome of any request for 2 x 200 Amp services?

And if demand metering was put forward by the PoCo, is there any way that this requirement/stipulation could be effectively resisted/fought (especially prior to the service being installed and actual load readings being taken)?

As far as 200A service......

Many areas REQUIRE it now, as far as the service box, never mind what the PoCo has coming to it, which might be 3 #18 wires if they could get away with it.

So if 200A service box means a demand meter as some unusual thing, there would be a lot of them here. I'm not sure the meters are made in a single phase version, either.

if you want to actually USE that much, maybe they might be upset, as the drops and local transformer might get pretty hot. And the "diversity" would be messed up. They can read their own bills, so there won't be any hiding or questions.

peak draw is another thing... that involves flicker, and may be limited for residential service in some areas, due to long lines. If you have a local transformer off a feeder, as the folks across the street have (from 3 phase, yet) it might be far less of an issue.

Short term start surge does not usually bother a meter, which may do a shrt term average over 15 or 20 minutes, but generally does not look at surges for ordinary meters. Some services and metering setups do.

"However, 100 Amps just doesn’t hack it when EVERY local Realtor that we have approached regarding resale modernizations tells us that local buyers are increasingly demanding electric heat & AC (and passing on properties with oil or propane). Can they all be wrong about this buyer mindset?

"So a 200 Amp service would appear to be a prerequisite regarding marketing this house in say 5 years time."

100 amps has been the minimum since just after WW-II.

The exceptions are those residences with all-gas cooking and heating, where as low as 40 amps/240 (a post-War residence) have been permitted, and as low as 30 amps/120 in one instance (a pre-War residence).

At the very large utility where I was once an EE in an earlier lifetime, all post-War residences, irrespective of cooking and heating fuel, had a minimum of 100 amps and #2 copper service conductors in 1-1/4" rigid conduit. Usually, the service drop would be #6 as the drops here are air-insulated.

Today, a residence with an outbuilding is more than likely going to require 200 amps, with 100 amps for the residence and 100 amps for the outbuilding.

More than 200 amps would be most unusual in coastal California, where the winters and summers are so relatively mild that there are relatively few heating and cooling days.

Irregardless of the demand metering, the Northwest R.E.C. (in pa)
has a form that states you will not attempt to start anything over 5 h.p.
as part of the intial hook-up.

To the other extreme...

Was in a house in N.Y. state ( a McMansion) that has a 400 amp service,
(1) 400 amp meter box with (2) 200 amp load centers next to each other.

Owner (an employee of Niagra Mohawk) stated that this is becoming the norm.

I find the R.E.C. easy to talk with, very casual and helpfull, Penelec on the other hand,
is like talking to a lawyer.

You really need to ask your local power company.

This varies so much from place to place, that its silly to get funny anecdotal stories from people all over the USA, and expect it to have any relevance to YOU.

You need to talk to a local electrician- they deal with this stuff every day, they know what costs what and what you can get away with, and they are NOT agents of the government or employees of the power company.

Everyplace is different.

I have never heard of demand metering on residences, but I am sure, somewhere, it might exist. In my area, demand metering on industrial drops doesnt start until you are using pretty huge amounts- I have 400 amps of 3phase and 200 amps of single phase on my farm (3 meters) and no demand charges have ever been levied on me.

But thats just me- in other parts of the country, with other power companies, I am sure people HAVE had to pay demand charges.

Per my discussion with a local POCO lineman, demand residential metering is something that is sweeping the USA bit by bit BUT the indication from the lineman was that rates are NOT going to change and there will be no charge for actual demand. They want to use the demand data simply to better monitor power fluctuations and customer needs to better balance systems and improve their efficiencies.

This came from a lineman, NOT an design engineer so take that with a grain of salt. I did mention that we are already billed for KVARS and demand issues in our bill and he did agree that even if they did try and bill us for demand, they would have to credit us back for something and would end up being the same anyway.

I suspect that as more and more stuff is electric these days and with really crappy PFs like SMPSs, they are having to beef up their systems bit by bit.

Someone mentioned that they didn't think they made a single phase demand meter, YES they do! Many years ago I worked in a NJ gas station while going to college. There was only single phase yet we had a demand meter because we had a number of Mercury Vapor lights. We turned them on one at a time plus we turned off the 5HP air compressor while turning on the MV lights. If we didn't do it the owner told us that we didn't when he got the electric bill!! We had 200 Amp service! Here in PA I know many commercial Single Phase applications that have demand meters. My daughter divorced and sold her house so I do not know much about her bill however I have seen my son's bill in GA and he is charged a demand! I had commercial power at my large machine shop. I had 1200 amp 480vac service and naturally had a demand meter, I paid a demand on draw over 5 KWH. That small amount is easily exceeded by a small shop in the home! Hollywood was great for that when they showed someone being executed in the electric chair! The amount of power required to toast some one in the chair wouldn't even move a demand meter!!
Sae8426 I doubt very much if your 30HP motor will cause lights to blink, yes it is a bit much for your 15K transformer and your house light might dim but not much for the transmission line of the power company. I doubt if you will be investigated but if you tell them it is possible you will get a demand meter. It will be determined by the policy established by your local supplier.
Here in my town we had a Penelec office with and engineer and linemen but it was eventually closed. When the office was here the engineer was easily reached and very helpful (now Good Luck getting any answer) I talked with the man man times and demand metering was one topic. Simply put the power company must have the transmission lines, transformers and generating capacity to deliver power on demand so during times of low demand that expense of having the power available when requested is not being paid for. (I'm not defending the demand charges only stating what I was told) Any of you that have paid a demand will know the demand bill is about the same as if the demand amount of power was constant for the entire month! Back in 2006 my electric rate for my shop was about $0.05/KW and my demand was almost $12/KWH do the math!
As to contacting the local power company about residential demand meters you might want to think that over too. Though I've never heard of anyone asking about demand from the local power company and then being investigated it might be possible! I have know many cases of questions asked of OSHA that prompted a visit from OSHA It may be a better idea to have a good friend call that has no demand issues inquire about power to put a small shop in his garage. If someone checks nothing will be found though I would ask this of someone not on my transmission line!

Hi Viper Do you really think the power company will go through the expense of putting a demand meter on everyone's home simply to get an idea of what the demand is? I'll bet the power company knows what the demand is for every transmission line. Ever drive by a pole with a meter attached and no home or business in sight? Power companies monitor line power usage to determine if they have a problem or someone is by-passing a meter.

There seems to be some conflation of "demand" vs "surge", or "peak"......

AFAIK, the "demand" is the largest power draw lasting over a certain time, such as 15 min or 20 min, the time varying with different poCo's. It makes sense to monitor that, as it is a draw long enough to affect the heating up of equipment, etc. And long enough to potentially mess up the "diversity", which assumes random action by several houses.

If you have any electric heat, a "demand" meter is almost the same thing as robbery, since you would always pay the demand rate..... what "furnace" or room heater is on for only a few minutes in winter?

Some of what is being mentioned sounds more like "surge" draws....... resulting from the turn-on of some lighting, or a large motor, such as the 5HP or whatever motor issues.

You already have large peak, or surge draws in your equipment. It is not uncommon for a piece of equipment including an SMPS to draw a peak 30x the actual full load draw at turn-on. Most manufacturers would put in an inrush limiter, but not all. Incandescent lamps have large turn-on surges, and other devices do also.

I am not aware of charges for transient peak draw. Start surges for large motors, and the draw of a large welding setup could be a different thing, as both may last longer.

We have 208 service at work, we draw large power from time to time over times of 30 min to an hour, but I do not think we have had any demand charges. That's "us" and that's "here", but it is a data point.

At this point in NY commercial setups get peak demand metering.

I would simply ask for an upgrade to a 200 amp residential service and do NOT
discuss your particular applications.

At all.

As an aside, there was one local peekskill house (which we almost bought) that
did indeed come with a 30 amp, 120 volt service. Gas hot water, gas stove,
oil furnace. Two bedrooms.

My wife actually did the closing for the folks who did buy it. The bank would not
write a mortgage on it with that service, it HAD to be upgraded to 240 volt, 100 amp
service before they would even talk about it.

Because it was being sold by an estate, the electricians working there were not
covered by homeowner's insurance for some reason, so they had to take out
a special liability policy for the time the workers were upgrading the service!

For about 20 years, I was in the electrical metering industry. Some of the trade shows/meter schools had displays of all the old metering devices, from Watt-meters to Ammeters to demand metering devices. They had piggy-bank meters where you would drop in a quarter (25 cents) and get some useable power. Mostly brass and cast-iron and definitely cool. The best display is at the North Carolina Meter School.

OK - please enlighten me as to what PoCo means?

Pole Company?


Google tried, but all they had was a bunch of sleepy tunes and C++ programming.


Add the werd "electricity" to the engine and came up pretty much empty handed....

Turn them around an make it Co-Op, then I follow. Especially with mention of the REA.

???


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POCO
Ox

PoCo = Power Company.

Man - I just couldn't git there on my own for some reason.


I kept seeing PUCO, but since he's in PA, instead of Ohio, Oklahoma, or Oregon, that wouldn't make sence enyway. His would be PUCP, and even then wouldn't be involved (only slightly) on this question, so I was


Man - just needed that extra set of eyes once aggin...

Mebee I need to git my eyes checked? DMV says their OK, but ...



------------------

Think Snow Eh!
Ox

It's OK OX, we will let it slide just this once but you are now on mind reading probation.


Most of the time, I just refer to them as the PC but POCO seems to be more industry accepted.

JST Here in PA a demand meter will measure surge and you will get charged for motors starting but unless you have very large motors the demand is not very large. Basically a demand meter will average the amp draw for 15 minutes and use that average for an hourly rate. Often welders thought that they could weld for 14 minutes stop for 1 minute and weld again for 14 minutes and not get charged a demand but that's not the fact! At least that's what I was told but the Pennelec (my power company) Engineer. I also had time of day . Problem being if you ran for example a 10HP motor for 15 minutes and it was pulling the full 28Amps there would be a $90 demand charge for the month plus the usage charge of 10 cents for the 15minutes. Furthermore if for example I decided to go on extended vacation and not show up the following month I would be billed 60% of my demand even though nothing was turned on! Most of the time my demand charge was about equal to my usage charge so the demand meter doubled my bill!
Frank

Ox said:

Man - I just couldn't git there on my own for some reason.


I kept seeing PUCO, but since he's in PA, instead of Ohio, Oklahoma, or Oregon, that wouldn't make sence enyway. His would be PUCP, and even then wouldn't be involved (only slightly) on this question, so I was

Click to expand...

No problem Ox, I once did a install drawing for a welding machine, and the company
(from Ontario, Canada) had labeled the input connections for the electricity
as "Hydro", and it also had connection's for cooling water, labelled as "water".

I knew what they meant (watching t.v. from ontario all the time) but it wasn't
very clear to the maintanance people hooking it up.