pwp: grid impacts and utility bills

Pasadena Water and Power

Electric Vehicle Workshop

March 31, 2012

Pasadena Water and Power Electric Vehicle Workshop

Topics

• Plugging in to the Grid at Home

• Charge at Night…late at night (utility impacts)

• Cost of Gasoline vs. Home Charging

• PWP Incentives

• More Information

> www.PWPweb.com/EV

> Call the Program Answerline: 626-744-6970

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Plugging In to the Grid at Home

• Your options> 120 Volt wall socket (slooowwww)

> 240 Volt “Level 2” charger

• You will need permits for electrical work> City Permit Center

• You may need to upgrade your service panel> PWP Utility Service Planning

> Could trigger “undergrounding” requirement - $$$

• We can help guide you through> PWP Answerline: 626-744-6970

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Sidebar: Energy vs “Demand”

• Residential bills based on energy use (kWh)

• Demand (or power) is the maximum rate of energy delivery to the customer (kW)

> Utility equipment and your electric service panel must

be sized to meet your maximum demand

• A microwave oven uses about 1 kW of power

> If you run it for 1 hour, then you consume 1 kWh

• A 100 W light bulb uses 0.1 kW of power

> If you run it for 10 hours, then you consume 1 kWh

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Power Demand (kilowatts)

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Typical Level 2

charger demand


Charge at Night (Late)

• Adding a Level 2 charger can be like adding another house!

• Delay charging to midnight - unplug by noon:

> Reduces strain on transformer feeding your house

> Reduces costs to procure energy

> Reduces need and cost to upgrade distribution

circuits and build new power plants

> ….Everybody saves!

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= !!!


Home Charging Scenarios


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Date & Time

De

ma

nd

(K

W)

Uncontrolled

Delayed

Off Peak

House Load

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Utility Infrastructure Impact

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EV “clustering” can

overload transformers

• Sparse EV adoption will not be a problem

• However…


Cost of Gas vs Home Charging

• 800 miles/month (9,600 miles per year)

• Gasoline: $80-200 per month

• PWP Electricity: $35-70/month> EV efficiency: ~0.375 kWh/mile => 300 kWh/month

> Electric costs varies significantly depending on your current electric usage

> Time of Use (TOU) rates may reduce electric bills

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Vehicle Type Mileage $4/gallon $5/gallon

Efficient Car 40 mpg $80 /month $100 /month

Less Efficient 20 mpg $160 /month $200 /month


Time of Use Rates

• Rates reflect varying demand on electric system and costs to serve customers:> Time of day:

“On Peak” (daytime) – highest energy use

“Off Peak” (night) – lowest energy use periods

> Season:

Summer (June-Sept) – highest energy use

Winter (Oct-May) – lowest energy use

• Designed to encourage “Off Peak” energy use:> Lower costs, environmental impact

> Increase system reliability

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“Standard” TOU Rates (¢/kWh)

• Customer pays for meter installation - $400+

• Could save $2.20/mo by charging Off Peak…

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TOU Period Summer WinterAnnual Average

On Peak 12.45¢ 8.89¢ 9.85¢

Off Peak 8.13¢ 7.89¢ 7.99¢

Flat Rate 9.32¢ 8.40¢ 8.73¢


“Experimental” TOU Rates

• Coming soon – watch PWPweb.com/EV

• Limited time offer for Residential EV owners

• May not be available for solar customers> Technology and billing issues must be resolved

• Residential TOU meter installation fee waived

• Rates are set relative to the regular “seasonal-flat” Residential electric rate:> Lower cost “discount rate” at night

> Higher cost “premium rate” during the day

> Same discount or premium every day of the year

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“Experimental” TOU Rates

• Two options choose from:

> EV-1: Discounted night and morning rates are limited

to a one year “trial period”

> EV-2: Greater savings for charging at night…

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TOU Period EV-1 EV-2 Hours

On Peak +0 ¢ +4 ¢ Noon - 9pm

Mid Peak -1 ¢ -2.5 ¢8am – Noon9pm – Midnt

Off Peak -2 ¢ -4.5 ¢ Midnt – 8am

Savings* ($/mo) $ 6/mo $ 13.5/mo*Savings vs flat rates when charging EV Off Peak


Experimental TOU Rates

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Flat

Rate


TOU Rates Encourage Off Peak

Charging and Household Energy Use


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Date & Time

De

ma

nd

(K

W)

Uncontrolled

Delayed

Off Peak

House Load

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Off Peak

(Midnt - 8am)

On Peak

(Noon - 9pm)

Off Peak

(Midnt - 8am)

Mid

Peak

Mid

Peak


PWP Incentives

• Residential Customers> No cash incentives for EV or charger

> Free energy use audit upon EV purchase

> “Bonus” incentives for energy efficiency retrofits

> Experimental TOU rates with Off Peak discount

> Waive TOU meter fee

• Commercial Customers> Cash incentive of $500 for installing L2 chargers

accessible to public, limited to retail, entertainment and hospitality locations (malls, restaurants, theaters, parking lots)

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More Information

• Pasadena Process and PWP Incentives

> PWP Website: www.PWPweb.com/EV

> PWP Answerline: 626-744-6970

• Other Resources

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Summary

• Plugging in to the grid at home> PWP can help with the process

• Charge at night…late at night> Reduces costs and strain on infrastructure

• Filling the tank with electricity

> $35-70 per month for most residential customers

• PWP Incentives

> TOU rates and additional energy efficiency incentives

• More Information

> www.PWPweb.com/EV

> Call the Answerline: 626-744-6970

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