NOTL Hydro preparing for transition to electric vehicles

According to the stated objectives of the automobile manufacturers, we are moving towards a world where almost all new cars will be electric vehicles.

GM has a stated goal of all new vehicles being electric by 2035, Toyota has an aim of 70 per cent of all sales being electric by 2030 and hundreds of billions of investment dollars in electric vehicles have been announced by the automobile manufacturers.

There is much about this future world we do not know (it is in the future) but we can predict that most of the power for all these electric vehicles will come from the electricity grid. Based on this, we have analyzed the impact of widespread EV adoption on our local system as well as the provincial grid. There are four specific parts of the system we looked at:

1. The local transformer and upstream distribution system
2. NOTL Hydro’s access to the provincial transmission grid
3. The transmission grid itself
4. Provincial generation

Coincident demand

When discussing electricity, it is important to distinguish between how much electricity is used over a period of time (consumption) and how much is used at any one time (demand). Most of the risk is with too much demand, and electric vehicle charging overloading the system at a point in time.  For instance, if everybody plugs in their car when they arrive home from work, then what is already the peak demand at around 5 to 6 p.m. will get much worse.

The local transformer and upstream distribution system

Transformers are the green boxes (for underground systems) and grey cans on the poles (for above ground systems) that step down voltage from 16,000 V to the 120/240 V used at most houses. There are over 2,000 of these in NOTL. Each transformer provides power for up to 12 homes. Transformers are sized and installed on the assumption that an average house uses up to around 4 kW of power at any one time.

An electric charger uses much more power than the average household when it is in use. An average level 2 charger can use up to 7 kW. This chart is extreme, as it shows the charging of a Tesla, which has a higher charging demand than most other vehicles. At its peak, the combined demand of the house and charger is over 17 kW. Should you have several electric vehicle chargers operating at the same time, the local transformer could be overloaded. This creates the risk that the transformer could fail, creating a local power outage. Even if NOTL Hydro identifies that a transformer is overloaded, there is the risk that we may not be able to get replacements. Electric utilities will all have this issue, so will all be upgrading their transformers at the same time across North America.

We analyzed a number of scenarios, depending on how many chargers on a transformer were operating at any one time.  The results were promising. The number of transformers at risk of over-loading was fewer than expected, so should be manageable. One of the fortunate reasons for this is that NOTL Hydro has been oversizing their green pad-mounted transformers to meet potential demand from unrealized electric heating and air conditioning load for many decades.

As well, most of the transformers at risk were the grey pole-mounted ones used for overhead services.  This overloading can be corrected by either replacing the transformer with a larger one or adding an additional transformer to the system and rewiring the local connections.  As the wiring is all overhead on poles this is much easier than with the underground system.

The upstream distribution system, including low voltage and high voltage wiring, also needs to be considered with increased local load. NOTL Hydro has specified low voltage wire to accommodate 200 amp residential services for decades. Existing 200 amp services are very likely able to accommodate the addition of an electric vehicle charging station in a residence. A service size upgrade may be required for additional loads beyond a single electric vehicle charging station installation.

Similarly, primary high voltage wiring has been sized beyond the installed capacity of the equipment serving the community. In most cases, there is enough room on primary feeders for the additional electric vehicle charging load.

We do ask that if you buy an electric vehicle and install a charging station, please let us know so we can check the local transformer and upgrade it if necessary.

NOTL Hydro access to the provincial grid

As a result of investments over the past 15 years, NOTL Hydro has significant transformation capacity to take power from the provincial grid and convert it to our local voltages. In aggregate we have around 150 MW of transformation capacity and the current peak is around 50 MW. This extra capacity was put in place to provide a redundant source of power for the whole town but is also available to manage future growth like from electric vehicles.

There is another potential source of power to service electric vehicle charging, and that is additional solar power. Since the ending of the provincial contracts, the number of new solar installations in NOTL has been limited, but as the costs of solar continue to fall, that is changing.

Transmission grid

The transmission grid is responsible for bringing power from the various large generators (hydro plants, nuclear power plants, large solar and wind farms) to the local utilities that then distribute the power. The actual demand for power from the transmission grid has been falling since the 2007-2008 recession. It is only now starting to pick up. As a result, only limited new investments in the transmission system have been required. While I have the greatest respect for Hydro One’s technical staff, the combination of NIMBYism, multi-year timelines for projects, regulatory procrastination and bureaucratic inertia could make the transmission grid a chokepoint.

NOTL is fed off a 115 kV line that runs from the Beck power plant, through St. Catharines and eventually connects with a 230 kV line.  There is currently some excess capacity available on this line, but that can change quickly with growth. The worry is that if NOTL is competing with the rest of Ontario for upgrades to the transmission grid, it might end up lower in the queue.

Provincial generation

NOTL Hydro analyzed the impact of every vehicle in NOTL becoming electric. Our estimate, based on some very high-level assumptions, was that the increase in demand would be 25 per cent. While this is high, it is not extraordinary or unmanageable. Ontario has managed much higher growth in demand for electricity in the past.

I discussed this in more detail in my March 15, 2022 blog at https://www.notlhydro.com/electric-vehicles-and-electricity-demand/. One of the reasons why the increase in generation needed is not higher is that electric vehicles are much more energy efficient than those with internal combustion engines, which waste a lot of energy, and that is all the excess heat radiating from the engine.

Planning ahead – next steps

NOTL Hydro is confident it can manage the transition to electric vehicles in NOTL. No customer should be worried about their ability to charge a new electric vehicles, though again, we do ask if you could let us know if you have installed an electric vehicle charger so we can check the local infrastructure.

Provincially, there is more of a challenge, not the amount of new electricity, but if it is all wanted at the same time. If the demand for electricity for electric vehicle charging largely happens in the late afternoon or early evening, then there is a real danger the transmission system and/or the generation capacity cannot cope.

The good news is the Ministry of Energy is fully aware of this challenge and is working to try to address it. One of their first steps will be the introduction of new rates later in 2023 that will have very, very low rates at night offset by higher rates in the late afternoon peak times. These new rates are optional, but if you have an electric vehicle you should look into them. Charging your electric vehicle later at night will make it even cheaper to drive.

Beyond that, I am anticipating there will eventually be spirited discussions as to whether electric utilities will be allowed to restrict the charging of vehicles at certain times to prevent overloading the provincial system. This could mean giving the utility access to control, limit or program the customer-owned charger; potentially in return for a discount.  Alternatively, it could mean penalties if charging is being done at the peak times or the new optional rates being implemented in 2023 could be imposed.  It will all be about managing the demand for electric vehicle charging in the least costly manner.