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Increasing electrical service to the home

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gpetti

Active Member
Supporting Member
Nov 6, 2013
1,643
122
Calgary, Canada
I imagine this varies tremendously between countries, and even here in Canada between provinces and cities but I thought I would share this as I know there will be helpful input. I have a 150 amp service. All heating in the house is gas but I do have a hot tub, AC, in floor heating, electric stove, and cook top, electric dryer and the usual lighting and electrical appliances. I bought an HPWC for the house. I did some tests to seem how high the draw might go and I managed to hit 110 amps with most of the major items turned on. Realistically when I'm charging we won't be running ovens or cook tops so I'm probably safe to charge at night up to a reasonable high level of current flow. That being said, I felt that having a 200 amp service would make more sense particularly as this might not be the last electric car I buy and I don't really want to have to have to bring out a calculator prior to turning on appliances in the future. My electrician determined that the cable to the house was not sufficient to allow more than 150 amps so I asked the electrical provider Enmax to provide a quote to increase the service. What they ultimately told me was that for a previous customer they had to dig up two driveways to put in a new cable and it cost $50,000. For our house we would need 4 driveways dug up so by extrapolation this would probably cost $100,000. Not exactly scientific but it seems ludicrous to me that essentially I'm stuck with whatever service was provisioned for the original house. If I had a spare 100,000 to throw around I'd buy another Tesla (though I probably couldn't charge it :) ). I have no idea how these cables are run but the implication is that each service is a separate cable from the nearest transformer and that they more or less run in the shortest possible route. Does this sounds normal or reasonable? I'm told that I'm probably lucky to have 150 amp service as apparently many residences are likely to be 100A. I guess this is mostly just an issue for heavy charging with the HPWC but it does seem that increased usage of electricity could have some barriers. I'm going to look at Solar but I presume this won't help me with the service size unless I setup my car to use stored solar power off grid.
 
That seems like a lot. My power company floated ~$5k as a basic cost of getting a second 150A/200A feed to my house. They seemed to intimate that it would only be marginally more expensive than upgrading my 150A feed to 200A. And that involved going under one (my) driveway. (Granted the whole run to the transformer is only about 300 feet in my case).

Directional boreing machines are fairly common, you can easily go across roads and driveways without damaging them at all.
 
> All heating in the house is gas [gpetti]

As in super cheap natural gas distributed by a decent sized pipe? If that is the case you might consider a new co-generation plant to provide electric plus the waste heat from engine goes to water & house heating systems. Kiss the grid goodbye.
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At those prices, sell your house and buy/build one more to your liking.

As for your usage, I don't quite grasp why you think larger service is needed? Do you often drop by home to charge and rush right out again?

I didn't buy the twin charging option because I didn't see any need to charge in a hurry at home. That has proven valid as I charge at 20A on my UMC starting at 2 AM and its always ready when I am. Also if I had hot tub or was often using the electric dryer or oven then its a very safe bet those are not in operation at 2 AM.
 
I have it even worse, only 100 amps service for me. That's why I didn't go for the twin chargers. You might consider ditching the electric dryer and electric stove right off the bat. I personally favor gas stoves over electric ones. For when you get your second Tesla :) , have one charge station max out at 24 amps and the other at the full 80amps assuming you won't need to charge both vehicles at max amps at the same time. Even 16 amps at 240volts is plenty to charge overnight.
 
I also looked into installing a separate meter just for the Tesla. My electric company will provide electricity at 1/3 the rate if it is only used for electric cars. I gave up on this idea when two electricians quoted in the $6000 range and a third wouldn't even bid on the job.
 
That seems like a lot. My power company floated ~$5k as a basic cost of getting a second 150A/200A feed to my house. They seemed to intimate that it would only be marginally more expensive than upgrading my 150A feed to 200A. And that involved going under one (my) driveway. (Granted the whole run to the transformer is only about 300 feet in my case).

Directional boreing machines are fairly common, you can easily go across roads and driveways without damaging them at all.
Thanks. That sounds much more reasonable.
Apparently we haven't invented directional boring here unless it is to drill for oil :)

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If you have conduit under your driveways it may be as simple as pulling a new feeder wire. You would need to check the capacity of your existing panel(s) to determine if they are capable.

That is what I assumed they could do. I'm thinking that I may want to push for more details and make sure I didn't just hit a front line person who didn't want the hassle.

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> All heating in the house is gas [gpetti]

As in super cheap natural gas distributed by a decent sized pipe? If that is the case you might consider a new co-generation plant to provide electric plus the waste heat from engine goes to water & house heating systems. Kiss the grid goodbye.
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Trying to get away from combustion energy source... I read somewhere that natural gas for heating is pretty efficient but for generating electricity, not so much. On the other hand if I'm using natural gas I won't get shunned by the oil and gas community here.

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At those prices, sell your house and buy/build one more to your liking.

As for your usage, I don't quite grasp why you think larger service is needed? Do you often drop by home to charge and rush right out again?

I didn't buy the twin charging option because I didn't see any need to charge in a hurry at home. That has proven valid as I charge at 20A on my UMC starting at 2 AM and its always ready when I am. Also if I had hot tub or was often using the electric dryer or oven then its a very safe bet those are not in operation at 2 AM.

Love the house - from what I can tell I would have to build one from scratch and specially request a 200 amp service. I believe I can make this system work even if I do use the higher amp charge rates; however, as I may expand my electrical footprint in the future I didn't want to reach a point where I have to run around and make sure things are turned off prior to charging. I'm trying to work out what the worst case high water mark might be. The hot tub kick in as required to maintain temperature as do some other heating items and of course the AC. Typically we are not cooking in the middle of the night though I guess we could have timed cooking as well. I think that normally if the hot tub is doing heavy duty the AC is probably not required and the chances of cooking or drying at the same time as charging is all remote. My ideal would be that someone less involved that I (say my wife for example) wouldn't have the opportunity to find a way to trip the house breaker if possible. If a 200 amp service was relatively cheap it seemed worthwhile but clearly I need to re-think this. As I'm ultimately interested in solar options that would be a much better way to spend money. Could probably create a system to drive the whole house for much less than 100K.

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I have it even worse, only 100 amps service for me. That's why I didn't go for the twin chargers. You might consider ditching the electric dryer and electric stove right off the bat. I personally favor gas stoves over electric ones. For when you get your second Tesla :) , have one charge station max out at 24 amps and the other at the full 80amps assuming you won't need to charge both vehicles at max amps at the same time. Even 16 amps at 240volts is plenty to charge overnight.

Strangely as I live in a plentiful NG area, gas dryers are not very common. Gas cooktops (not so much ovens) are pretty popular but my wife claims she might set herself on fire. Having watched her in operation with an electric stove I decided on an induction cooktop instead.
Thanks for the additional suggestions.
 
Get yourself a gas dryer - they are way more efficient and nicer on the clothes.

Usually the conduit used to pull your service wires is sized exactly for the service size, so it is unlikely it could be used to pull larger wires.

When you measured your usage, was that 110A on EACH 120V leg? That seems like a lot.

$50K is a ridiculous estimate. But digging up neighbor's driveways isn't going to endear yourself to anyone. I wonder if you could go out to the road and back. In which case, I'd see if I could hire my own trenching contractor and see if the power company would allow you to dig your own trench and lay your own conduit (as per their specs). If so, you could probably do the job for $5K.
 
When you measured your usage, was that 110A on EACH 120V leg? That seems like a lot.

We put an ammeter on one of the wires coming into the main fuse panel. Then I turned on electric oven, cook top, AC, Hot tub and an in floor electric heater. I forgot to put the dryer on. I did some other measurements with the oven and cook top off (as they are least likely to be on at the time when I charge). I don't have those measurements handy but they were obviously more reasonable.
 
The Service Planner at So Cal Edison warned me that I may need to trench etc. I said I was interested and after he visited he determined the existing infrastructure would work. My second meter install starts Monday 2/24/2014. I do need to have some gas lines adjusted ( about $200). The electrical work with permit and running about 120 feet to the garage will cost $3,100. The will be some patch and painting ( unknown) . The HSWC cost $1,200. All in I guess I will be at $5,000 or so.

Wonder what bumps in the road I may encounter.
 
The rough answer - it depends. In my case, the power company paid for everything except the installation and connection of the new meter pan they supplied to me. They pulled new compact conductors, etc.

I understand that situation is different elsewhere. I have always suggested that you call the power company, explain that you're going to be doing a lot more business with an EV, and use that as justification to see if they will pay for it.
 
The rough answer - it depends. In my case, the power company paid for everything except the installation and connection of the new meter pan they supplied to me. They pulled new compact conductors, etc.

I understand that situation is different elsewhere. I have always suggested that you call the power company, explain that you're going to be doing a lot more business with an EV, and use that as justification to see if they will pay for it.

Thanks, this might be worth a shot though I have the situation where the company that is responsible for the service provisioning is only one of two (maybe more) companies that I can buy the electricity through. As luck would have it (actually not luck so much as economics) I'm using their competitor who also provides me with gas. Maybe that explains their prohibitive estimate. Too cynical?
 
Thanks, this might be worth a shot though I have the situation where the company that is responsible for the service provisioning is only one of two (maybe more) companies that I can buy the electricity through. As luck would have it (actually not luck so much as economics) I'm using their competitor who also provides me with gas. Maybe that explains their prohibitive estimate. Too cynical?

No, not too cynical at all. We saw this type of "coopetition" in the telephone/Internet CLEC days.
 
> I read somewhere that natural gas for heating is pretty efficient but for generating electricity, not so much. [gpetti]

Well then it must be true! Especially if it is propaganda sourced from electric power interests.

Keep in mind that cogen plants are designed specifically for piped natural gas, not propane or butane, etc so they are not some cobbled up compromise. That virtually *all* the energy from the ng gets to be used onsite which includes most of the heat in the exhaust stream as well as all heat from the engine & alternator cooling system. You are way ahead of that 250 megawatt power plant down by the river which has NO use for all their excess heat so they dump it into the river water. The ICE will 'last forever' running as it does on dry fuel which does not affect the cylinder wall lubrication.
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> I read somewhere that natural gas for heating is pretty efficient but for generating electricity, not so much. [gpetti]

Well then it must be true! Especially if it is propaganda sourced from electric power interests.

Keep in mind that cogen plants are designed specifically for piped natural gas, not propane or butane, etc so they are not some cobbled up compromise. That virtually *all* the energy from the ng gets to be used onsite which includes most of the heat in the exhaust stream as well as all heat from the engine & alternator cooling system. You are way ahead of that 250 megawatt power plant down by the river which has NO use for all their excess heat so they dump it into the river water. The ICE will 'last forever' running as it does on dry fuel which does not affect the cylinder wall lubrication.
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To be honest, I've never heard of these and no one has suggested them - even though our whole economy is driven by oil and natural gas. Obviously doesn't mean we can't get a cogen plant here but if I'm going to invest in something to supplement my grid usage it would probably be solar.
 
To be honest, I've never heard of these and no one has suggested them - even though our whole economy is driven by oil and natural gas. Obviously doesn't mean we can't get a cogen plant here but if I'm going to invest in something to supplement my grid usage it would probably be solar.

Actually doing both can be good, and they are not mutually exclusive. Using the waste heat off of an NG powered generator is comparable to PV production in terms of environmental payback. Compare the financial paybacks and invest where it makes sense.

Honda Worldwide — Creating a new residential paradigm
 
I think I have 200a service at my house but I'm not sure, I should take a better look at the panel(s) when I'm home

I got rid of my natural gas lines and replaced the gas heat with a heat pump (I live far enough south that it makes sense to do so) and between that, insulation in the attic and some weatherstripping I reduced my heating bill by 75%.

Of course in the process I increased my electrical consumption in the winter and they added a new sub panel as the new heat pump can draw more at max load than the old electric AC did. Still there are plenty of other changes I have made or plan to make that will reduce my maximum load.

High efficiency front loading steam clothes washer reduces hot water usage and uses less power itself spinning the tub (direct drive, less water = less weight to move) still not as big of a factor compared to others in this post but worth doing.

Heat Pump water heater, uses 1/3 to 1/2 the energy of my old electric water heater and often does so by running the heat pump for longer periods at lower power draw (less amps in that mode) though this isn't as good of a deal for northern climates unless your water heater is in a heated space to begin with.

LED light bulbs, my house has something north of 50 sockets and if I turned them all on at once with 60w bulbs we are talking 25a, a few years ago all the bulbs were CFLs and most are 9w or 13w turning all of them on is down to 5a a reduction of 20a in maximum load, I'm moving to LED bulbs rated at 3w or 6.5w so we are talking about a max load around 2a. If your home has lots of incandescent bulbs you can reduce your max load by double digit amps just by replacing light bulbs.

TVs I still have a couple of tube based 27" tvs in use and a few flat screen LCD TVs that each draw hundreds of watts. It's easy now to find TVs north of 40" that draw less than 1/3 the power my old TVs do. Depending on the age and number of TVs this could save you as much load as replacing light bulbs.

As I add electric cars I'll be adding EVSEs that I expect will offset ever bit of the savings I made from the other categories but if you are on the edge or just concerned it might be worth looking at how you can cut your power draw in other parts of the house before having to upgrade your incoming service to the house.
 
...I have a 150 amp service. All heating in the house is gas but I do have a hot tub, AC, in floor heating, electric stove, and cook top, electric dryer and the usual lighting and electrical appliances. I bought an HPWC for the house. I did some tests to seem how high the draw might go and I managed to hit 110 amps with most of the major items turned on... Enmax to provide a quote to increase the service. What they ultimately told me was that for a previous customer they had to dig up two driveways to put in a new cable and it cost $50,000. For our house we would need 4 driveways dug up so by extrapolation this would probably cost $100,000. Not exactly scientific but it seems ludicrous to me that essentially I'm stuck with whatever service was provisioned for the original house.
I upgraded to 400A service about 4 years ago in anticipation of getting an EV. The utility didn't charge a dime since I dug the trench from the transformer to the house myself. The total cost was minimal (50' of 4" conduit, new main breaker panel and a connection to old main breaker panel to convert it into a subpanel feeding everything). Never-the less, the underground wiring to the garage limits that subpanel to 50A. Although I'm in the middle of bringing 200A out to the garage so I can run the air compressor when charging the EV's, long story short, I haven't been feeling much of a pinch charging 2 EV's (Leaf and S) via my 30A J1772 EVSE (I dial the S back to 20A to keep my old wiring in the garage on the cool side).

Considering the hassle and expense of your situation, it might make sense to see how you like charging at 30A. So far I have never had an issue with the typical mileage I put on the car during a day. The Tesla Charge Time and Cost Calculator shows that a 200 mile recharge takes only about 6.75 hrs at 40A. At 30A it would take around 9 hours, which is enough time to finish the charging well before I'm ready to head out again in the AM.

Tesla charge time and cost calculator.JPG
 
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