Effect of BEVs on Electric Grid

…Effect of BEVs on Electric Grid…

What will be the effect of 250 million BEVs on America’s electric grid in 2050?

What will it cost to allow the electric grid to safely supply 250 million BEVs with the power they need?

And, is it even possible to transition the grid to accomplish this objective?

Each of the following components need to be examined.

• Charging stations
• Distribution and substation transformers
• New power plants
• Transmission lines
• Underground cables

Charging Stations

Tesla has 1,772 supercharging locations, i.e., stations in North America, with around 10 charging stalls at each location. On this basis, Tesla has approximately 17,720 charging stalls.

Tesla’s total cost for their existing system, assuming power entrance costs of $100,000 per station and $20,000 per stall, would have been around $530 million.

There are approximately 125,000 gasoline service stations in the United States, each with at least eight fueling pumps, needed to service 250 million ICE vehicles. 

While the use of home charging may reduce the need for this many locations, the length of time required to charge each BEV is 30 minutes, or six times the amount of time required to fill an ICE vehicle’s gas tank, which could increase, rather than reduce the number of stations needed.

Using 125,000 gasoline service stations as the basis for the number of locations required, and Tesla’s cost of $530 million for 1,776 locations, we can divide 125,000 by 1,776 Tesla locations to establish we need 71 of Tesla’s existing network of locations to service 250 million BEVs, at a cost 71 times $530 million, which is $37.5 billion.

Distribution and substation transformers

There are two distinct populations of distribution and substation transformers.

• First, there are the suburbs and small towns spread across the country. These areas are predominantly blanketed by single family homes, with a smattering of apartment buildings, with commercial and light manufacturing centered in areas zoned for these activities.
• Next, there are the big cities where most people live in apartment buildings and park their cars on the street.

These must be analyzed separately.

In the first instance, distribution transformers typically serve four homes, so it is the combined load from all four homes that must be carried by the distribution transformer.

Substation transformers supply distribution transformers and as the load on the distribution transformers increases, the load on the substation transformers also increases.

Ultimately, nearly all Distribution Transformers (DTs) serving homes and apartments outside of large cities, will have to be replaced to accommodate 250 million BEVs. Many substation transformers, or network transformers in some big cities, will also have to be replaced.

With one DT serving an average of four homes, the number of DTs that will have to be replaced for single family homes is 25 million.

There is the cost of the new transformer, the cost of the utility crew to install the unit, and the cost of re-inventorying or disposing of the old transformer. 

While utility practices vary, the cost of changing out one 50 KVA distribution transformer, and replacing it with a 100 KVA unit is around $20,000.

Using $20,000 as the basic cost, the cost of replacing 25 million DTs is over $500 billion.

There are approximately 15 million apartment buildings of which approximately 5% are located outside major cities. The cost of replacing the larger DTs in local communities will be around $41 billion.

If only 15% of the  55,000 substation transformers become overloaded due to overloaded distribution transformers, the cost could be $9.9 billion to replace the overloaded substation transformers. 

The cost to replace DTs and substation transformers in the country, excluding DTs in large cities, is approximately $551 billion.

New power plants 

NREL has published a study forecasting demand for electricity under two electrification scenarios.

• In the Medium scenario, demand increases to 5,800 TWh in 2050, servicing 186 million BEVs
• In the High scenario, demand increases to 6,700 TWh in 2050, servicing 242 million BEVs.

However, the Medium Electrification scenario includes space and water heating that account for 38% of all space and water heating in the country, while the High Electrification scenario forecasts that space and water heating will account for 61% and 53% respectively of the nations space and water heating requirements.

Assuming that the Medium scenario comes closest to reflecting electricity demand for 250 million BEVs, i.e., the electricity needed for space and water heating approximate the electricity required for the remaining 64 million BEVs, we can arrive at an estimate for the cost of adding additional generating capacity.

Current US power consumption is 4,127 TWh per year.

Assumptions for determining number of new power plants:

• Average size of a natural gas combined cycle (NGCC) power plant = 800 MW
• Capacity Factor (from EIA) = 54.4%
• Cost of NGCC power plants = $1,000 per KW

Using these assumptions, and demand of 5,800 TWh, 439 new NGCC power plants will be required to accommodate 250 million BEVs.

The cost of 439 NGCC power plants rated 800 MW is $351 billion. 

Transmission lines

Based on the Midcontinent Independent System Operator’s (MISO’s) transmission line cost estimating brochure, a short, 200 mile 230KV line will likely cost $600 million.

Since NGCC plants can be placed relatively close to where the demand exists, longer lines probably won’t be required.

Assuming that half the new NGCC power plants can be connected to existing transmission lines the cost of new transmission lines would be $132 billion.

(Wind and solar are excluded from this analysis because they cannot provide the needed capacity without adding the cost of large quantities of battery backup.The cost of wind and solar would be substantially higher for both the cost of building new power plants and the cost of transmission lines.)

Underground cables

Underground cables are used extensively in suburban areas, and while there is a high probability of cable failures resulting from the increased load, there is no way to estimate the cost.

Similarly, it’s not possible to determine how many overhead lines will have to be replaced.

Summary

Costs to accommodate 250 million BEVs are summarized here:

• Cost of charging stations $37.5 billion
• Cost of replacing distribution and substation transformers $551 billion.
• Cost of new power plants $351 billion.
• Cost of new transmission lines $132 billion.
• Cost of new cables unknown.

Total cost is over $1 trillion.

Not addressed is whether it is even possible to obtain the necessary replacement transformers, since nearly half the DTs and nearly all the substation transformers have to be imported.

How many years would it take to replace all 25 million DTs to accommodate 250 million BEVs? 

Utilities typically use fewer than one-million DTs in a year, however, suppliers could probably provide somewhat more if needed. 

With this in mind, replacing 25 million DTs certainly cannot be done in a few years, and will probably take a decade or longer. A sufficiently high volume of DTs are not being built today to rapidly upgrade the grid. 

As for substation transformers? Lead times are over a year, indicative of an additional supply chain problem.

Upgrading the grid to accommodate 250 million BEVs is prohibitively expensive, and may not even be possible.

This article is a summary of a report that goes into greater detail. and provides the sources for all the information contained in this article. 

The free report, Battery Powered Vehicles: Their effect on the electric grid, is available at bit.ly/3xUV7P0

Let others know about this article by using this link in an email bit.ly/3IXjZe5 

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