The Service Upgrade

If you live in an older house and want to make updates, do a remodel, or change appliances, invariably someone, usually a contractor or electrician, will say you need to "upgrade your electric service".

But do you, really? What’s involved, how much does it cost, and why would you need to upgrade your service?

The argument that says you need to upgrade is this: If you use all of your electrical appliances at the same time, you’ll overload the wiring to your house. Is this dangerous? Maybe; but most likely what will happen is your main circuit breaker or fuse will trip, cutting off all the power to your house until you reset it.

That seems mighty inconvenient. But what are the chances you’ll ever use all of your electrical devices at the same time? Very low, (only 2% of 22,000 homes in Californian used more than 88 amps anytime in a year, based on smart meter usage data) but still it could happen. This is where the “load calculation” comes in, and it’s written into the National Electrical Code:

ARTICLE 220 - BRANCH CIRCUIT AND FEEDER CALCULATIONS 220-1. Scope. This Article provides the basis for calculating the expected branch circuit and feeder loads and for determining the number of branch circuits required. 220-2. Calculation of Branch Circuit Loads. The load for branch circuits shall be computed in accordance with the provisions of this Section.

So here’s a load calculation I had done for my place:

(There are a number of online load calculators you can use to do this yourself, such as this and this.)

The load calculation above shows I can power these things for under 100 amps! There’s only 3 problems - (1) I’d have to convert my dryer from electric to gas, (2) I couldn’t upgrade to a Level 2 EV charger, and (3) my house isn’t actually 1686 square feet - it’s 2300!

So I needed to upgrade my service, right?

But then things got complicated.

First issue: The electric service to my house runs underground, across my driveway, through the yard, and across my neighbor’s back yard to a power pole near the edge of his property. Which means I’d need to tear up my driveway and my neighbor’s yard to do the service upgrade.

Second issue: Scheduling a service upgrade with PG&E, my utility. For an underground service upgrade, there are a whole bunch of specific requirements, such as outlined in the below specs:

In order to find out the costs of the upgrade, I would first need to pay PG&E $1,500 to start the process, without knowing final costs - but I’d still be on the hook for them!! (see the “Important” note on the invoice shown above). On the phone with PG&E, my contact estimated the total cost from PG&E would be about $10k just for the wiring and service installation - NOT including the cost of the trench, new conduit in the trench, or the electrical panel! My best guess was that it would be $25-30k all in. And based on my general contractor’s experience with another project, it would take at least a year to get the work completed!! PG&E by email estimated the engineering alone would be 6 months out.

This was crazy!! Spend $30k and wait over a year to avoid the improbable chance I use all my appliances at once and trip the main breaker? No way - there had to be a better way.

Turns out, there is. See Part 2 of this story.