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# Restricted Service Rates

Author: E.E. Kimberly

Because of the high peak demand on the systems of some power utilities and a substantial margin of unused capacity provided for emergency service, a restricted service is sometimes offered. The use of such service is permitted at certain hours only, when the generating-station load is normally low. An attractive rate is possible for such service, because of the curtailed investment required. Ideal loads for restricted service are water pumping, water heating, and other uses of electricity which are not necessarily synchronized with peak load operations.

SAMPLE RATE STRUCTURES Schedule A

Alternating and Direct Electric Current Power Service. The Service furnished under this schedule is Alternating Electric Current, Single or Three Phase, 60 cycles, 120-240 or 220-440 volts, and Direct Electric Current at 120-240 volts.

A minimum monthly charge of \$1.25 per kw or fraction thereof, of maximum demand, plus the following kw-hr charges for energy consumed.

 First 2,500 kw-hr per month at 2 1/2 cents per kw-hr Next 2,500 kw-hr per month at 2 1/4 cents per kw-hr Next 2,500 kw-hr per month at 2 cents per kw-hr Next 2,500 kw-hr per month at 1 3/4 cents per kw-hr Next 90,000 kw-hr per month at 1 cent per kw-hr Next 100,000 kw-hr per month at .9 cent per kw-hr

Schedule B

Character of Service:

115-230-460 volts alternating current.

Lighting will be included and will be billed at the power rate where the normal monthly power bill amounts to not less than \$125.00 per month, provided the lighting demand is not more than 25% of the power demand.

115-230 volts direct current.

AH direct current power service shall be supplied under this schedule and the lighting will be billed at the power rate under the following conditions:

A - where the normal monthly demand is 150 kilowatts or more.

B - where the normal monthly power bill is not less than \$125.00 and the lighting demand is not more than 25% of the power demand.

Minimum charge: Two dollars and fifty cents (\$2.50) net per month on all installations up to and including 5 hp of connected load. Above 5 hp of connected load, fifty cents (\$0.50) net per horsepower per month.

Demand: In determining the maximum demand of an installation under power schedule B, the following rules shall apply:

If an installation is less than 5 hp, its demand will be arbitrarily fixed at o hp. In installations of 5 hp to 25 hp, inclusive, the connected load in horsepower will be multiplied by 0.6 and the product will be considered the maximum demand in kilowatts. In installations of 25 hp to 50 hp, inclusive, the connected load in horsepower will be multiplied by 0.55 and the product will be considered the maximum demand in kilowatts. In installations of 51 hp to 200 hp, inclusive, the connected load in horsepower will be multiplied by 0.5 and the product will be considered the maximum demand in kilowatts. In installations of 201 hp and above, the connected load in horsepower will be multiplied by 0.45 and the product will be considered the maximum demand in kilowatts.

 RATES Hours use of Demand* Rate Hours use of Demand* Rate Hours use of Demand* Rate 1 to 50 \$0.0660 156 to 160 \$0.0345 266 to 270 \$0.0272 51 to 55 .0610 161 to 165 .0340 271 to 275 .0270 56 to 60 .0576 166 to 170 .0335 276 to 280 .0269 61 to 65 .0544 171 to 175 .0330 281 to 285 .0268 66 to 70 .0512 176 to 180 .0325 286 to 290 .0267 71 to 75 .0480 181 to 185 .0320 291 to 295 .0266 76 to 80 .0465 186 to 190 .0315 296 to 300 .0265 81 to 85 .0450 191 to 195 .0310 301 to 310 .0264 86 to 90 .0435 196 to 200 .0305 311 to 320 .0263 91 to 95 .0420 201 to 205 .0302 321 to 330 .0262 96 to 100 .0415 206 to 210 .0299 331 to 340 .0261 101 to 105 .0400 211 to 215 .0296 341 to 350 .0260 106 to 110 .0395 216 to 220 .0293 351 to 360 .0259 111 to 115 .0390 221 to 225 .0290 361 to 370 .0258 116 to 120 .0385 226 to 230 .0288 371 to 380 .0257 121 to 125 .0380 231 to 235 .0286 381 to 390 .0256 126 to 130 .0375 236 to 240 .0284 391 to 400 .0255 131 to 135 .0370 241 to 245 .0282 401 to 425 .0254 136 to 140 .0365 246 to 250 .0280 426 to 450 .0253 141 to 145 .0360 251 to 255 .0278 451 to 475 .0252 146 to 150 .0355 256 to 260 .0276 476 to 500 .0251 151 to 155 .0350 261 to 265 .0274 Above 500 .0250 * See page 290

The company reserves the right to make tests at any time on the premises of any customer, and may, at its option, fix the demand by test, and the demand so fixed shall remain in force until the company makes other tests to determine the maximum demand. In fixing the demand of any installation, if there is a considerable portion of the load which is not used during the company's load peak, and if the customer will agree not to use this portion of the load during such hours as the company may specify, then the company may take this feature into consideration in fixing the maximum demand.

Discounts: Quantity discounts in accordance with the following schedule are applicable to Power Rate B and are determined by the gross bill, viz:

 \$100.01 to \$125.00 4% 950.01 to 1000.00 32% 125.01 to 150.00 6% 1000.01 to 1050.00 33% 150.01 to 175.00 8% 1050.01 to 1100.00 34% 175.01 to 200.00 10% 1100.01 to 1200.00 35% 200.01 to 225.00 11% 1200.01 to 1300.00 351/2% 225.01 to 250.00 12% 1300.01 to 1400.00 36% 250.01 to 275.00 13% 1400.01 to 1500.00 361/2% 275.01 to 300.00 14% 1500.01 to 1750.00 37% 300.01 to 325.00 15% 1750.01 to 2000.00 371/2% 325.01 to 350.00 16% 2000.01 to 2250.00 38% 350.01 to 375.00 17% 2250.01 to 2500.00 38 1/2 % 375.01 to 400.00 18% 2500.01 to 2750.00 39% 400.01 to 450.00 19% 2750.01 to 3000.00 39 1/2 % 450.01 to 500.00 20% 3000.01 to 3250.00 40% 500.01 to 550.00 22% 3250.01 to 3500.00 40 1/2 % 550.01 to 600.00 23% 3500.01 to 3750.00 41% 600.01 to 650.00 24% 3750.01 to 4000.00 41 1/2% 650.01 to 700.00 25% 4000.01 to 4250.00 42% 700.01 to 750.00 26% 4250.01 to 4500.00 42 1/2% 750.01 to 800.00 27% 4500.01 to 4750.00 43% 800.01 to 850.00 28% 4750.01 to 5000.00 43 1/2% 850.01 to 900.00 29% 5000.01 and above 44% 900.01 to 950.00 30%

Schedule C

Rate: The consumer's monthly bill shall be the sum of the demand charge and the energy charge.

Demand Charge:

First 10 kw of billing demand at \$30.00 per kw per year payable at the rate of \$2.50 per month.

Next 30 kw of billing demand at \$25.00 per kw per year payable at the rate of \$2.10 per month.

Next 160 kw of billing demand at \$21.60 per kw per year payable at the rate of \$1.80 per month.

Next 200 kw of billing demand at \$19.20 per kw per year payable at the rate of \$1.60 per month.

All over 400 kw of billing demand at \$18.00 per kw per year payable at the rate of \$1.50 per month.

Energy Charge: Energy used each month will be billed at the following rates: All kw-hrs in first quantity block at - 38 mills per kw-hr. All kw-hrs in second quantity block at - 19 mills per kw-hr. All kw-hrs in third quantity block at - 16 mills per kw-hr. All kw-hrs in excess of the sum of the three quantity blocks at 13 mills per kw-hr.

Energy Blocks

First Quantity Block: The kilowatt-hours in the first quantity block shall be as follows:

For corrected demands of:

From 5 kw to 25 kw - 350 kw-hr.

From 25 kw to 100 kw - 350 kw-hr plus 6 kw-hr for each kw of demand in excess of 25 kw.

From 100 kw to 400 kw - 800 kw-hr plus 4 kw-hr for each kw of demand in excess of 100 kw.

From 400 kw to 1600 kw - 2000 kw-hr plus 3 kw-hr for each kw of demand in excess of 400 kw.

From 1600 kw to 5600 kw - 5600 kw-hr plus 2§ kw-hr for each kw of demand in excess of 1600 kw.

Over 5600 kw - 15,600 kw-hr plus 2 kw-hr for each kw of demand in excess of 5600 kw.

Second Quantity Block: The kilowatt-hours in the second quantity block shall be four times the kilowatt-hours in the first quantity block.

Third Quantity Block: The kilowatt-hours in the third quantity block shall be four times the kilowatt-hours in the second quantity block.

Measured Demand: The measured demand shall be the average kilowatt capacity used by the consumer during the fifteen-minute period of maximum consumption during the month.

Power Factor: The company reserves the right to test or meter the power factor of the consumer's load and, if greater than 85% lagging, then the measured monthly demand shall be decreased for billing in the ratio that 85% bears to the actual power factor (in per cent) as determined.

The correction for all leading power factors shall be the same as for 100% power factor.

If the power factor of the consumer's load is less than 75% lagging, then the measured monthly demand shall be increased for billing in the ratio that 75% bears to the actual power factor (in per cent) as determined.

Corrected Demand: The measured demand in kilowatts corrected for power factor shall be the corrected demand. In no event, however, shall the corrected demand be less than 5 kw.

Billing Demand: The billing demand shall be the corrected demand in kilowatts of the current month, but not less than 50% of the highest billing demand of the preceding months.

Minimum Charge: The minimum bill in any month shall be a sum equivalent to the charge for 50% of the highest billing demand of the preceding eleven months.

Character of Service: This rate is available only to consumers having demands of 5 kilowatts or over.

Example 24-1. - A consumer uses 6400 kw-hr of energy in a month. The maximum demand as measured is 50.6 kw. Calculate the power bill under Schedule A.

Solution. - The total energy charge is found as follows:

2500x0.025 = \$ 62.50

2500x0.0225= 56.25

1400x0.020 = 28.00

Total = \$146.75

Demand charge = 50.6 kw at \$I.25 = \$63.75 Total bill = \$146.75 + \$63.75 = \$210.50 If the bill is paid when due, the charge is

\$210.50x0.95 = \$199.97

Last Update: 2010-10-06