If those figures on your Yaka meter have been mysterious to you or you probably think UMEME is cheating you, well, it’s time to get your hands dirty. It’s a bit technical. But like all things, it becomes easy if you understand the jargon and follow through.

## The basics: Understanding the units of electricity

The most basic units of measuring electricity are Voltage(V) and Current(I). Voltage is measured in Volts(V)s while current is measured in Amps (A). So what’s voltage and current? We don’t have time to rebound a physics class, so a familiar analogy of plumbing would suffice.

Think of water flowing from a tank at your home. The voltage is equivalent to the water pressure while current is equivalent to the rate at which water flows. Sounds simple now, right? Increase the water pressure(Voltage) and more water (Current) will gush out as you would expect.

So if you are a domestic user, your voltage is 240V for one phase. Industries need more power and are therefore supplied with three phases. Think of phases as being the different channels or pipes through which the water flows. The more pipes, the more water.

Now, Electrical power is measured in watts(W). It’s a result of multiplying Voltage(V) and Current(I). Again, using our analogy, we can have more power if we increase the water pressure or the water flow rate. Energy is the amount of power(Watts) used over a period of time(Hours). As you have guessed energy units are Watt Hours (Wh) and this is what you pay for on your monthly Umeme Yaka electricity bill.

## Before we start crunching your bill

1. Check the back plate of your appliance for the its electrical power rating in Watts (W). This is a measure of power that your appliance uses. The higher the figure, the more power your appliance uses and the bigger your power bill will be.

2. Estimate the usage (hours/time) of each appliance in your house. Find out on average how many hours(h) you use it per day. Then estimate the number of days in a month you use the appliance. The more hours and days you use your appliance, the bigger your power bill.

3. A unit of energy is measured in Kilo Watt Hours (kWh). That’s got by multiplying the power(W) of our appliance to time of use in hours (h) divided by 1,000 — remember kilo means 1,000.

4. Take logs of your meter reading so that you can compare notes with UMEME. We have written a comprehensive guide on how to use your Yaka prepaid meter, so those tips will come in handy.

Read more: Electricity Regulatory Authority (ERA) increases 2015 4th Quarter Umeme Power tariffs by 19.5%

## UMEME Yaka power rates and billing

Based on the latest UMEME power tariff structure (10th July 2019);

1. Umeme charges the first 15 units that you consume UGX 250 per unit.

2. The proceeding units are charged UGX 755.1 per unit.

3. Then there’s a monthly service fee of UGX 3,360

4. Umeme then charges 18% on VAT.

## How to Calculate

We will give a nice easy example so that everything else below makes sense. Lets use a Flat Iron as an example. If your flat iron uses 1000W (You can check on the back to see the wattage of your appliance) and you use it for 1 hour, You will get the wattage (1000W) multiply it by the number of hours used eg. 1 hour and divide it by 1000.

If you got the calculation right, then the answer should be 1 which is 1KWH. So if you use your 1000W flat iron for an hour, you would have used 1kWh ( or 1 unit) of electricity. You can further confirm this by noting the number of units on your Customer Interface Unit (CIU) or the Yaka meter as we commonly know it before using the 1000W flat iron and note the units left after using it for one hour. As you can see it’s not hard at all to do so let’s get a more applicable example below.

## Home appliances and average usage

So let’s say your house has;

1. 6 Philips energy savers each with a power rating of 11W. Let’s say you use them for 6 hours a day.

2. 1 Philips flat iron of a power rating of 1,000W. You iron for half an hour a day

3. 1 LG Microwave of 2,000 W which you use for quarter an hour a day.

4. 1 Samsung UN32EH4000 LED 32 inch Flat screen TV with power of 29 Watt. You watch TV for 4 hours a day.

Now we are ready to calculate your UMEME power bill

Appliance | No | Power rating(W) | Total power | Hours per day | Total energy per day (kWh) | No. of Days' usage per month | Total energy per Month |
---|---|---|---|---|---|---|---|

Philips energy saving Bulb | 6 | 11 | 66 | 6 | 0.396 | 30 | 11.88 |

Philips flat iron | 1 | 1,000 | 1,000 | 0.5 | 0.5 | 30 | 15 |

LG Microwave | 1 | 2,000 | 2,000 | 0.25 | 0.5 | 15 | 7.5 |

Samsung 32" Flat screen TV | 1 | 29 | 29 | 4 | 0.116 | 27 | 3.132 |

Total | 37.432 | ||||||

Total Monthly Meter reading | 37.432 | ||||||

First 15 Units | 15 | * | 150 | = | 2,250 | ||

Remaining Units (37.432-15) | 22.432 | * | 520.6 | = | 11,678.01 | ||

Total cost | 2,250 | + | 11,678.01 | = | 13,928.01 | ||

VAT | 18% | * | 13,928.01 | = | 2,507.04 | ||

Monthly service Fee | 3,360 | ||||||

Total Invoice Bill | 19,795.05 |

So that’s how you calculate your power bill. It’s a bit daunting, but if you want to save on your power bill and take charge of your usage, then this information is paramount. You can engage with us in the comments so we keep the conversation/lesson going.

Image: pakistantoday.com

Great and relevant piece! Thank you for demystifying physics for people like us. Isn’t this what they ought to teach us in O’level?

You are welcome Ochom. Yeah, this is Physics O’level indeed but we kind of all forget 🙂

woow i liked the piece, it so awakening and should be shared for all

Nice article. Does Umeme only use a flat rate (cost of electricity is the same irrespective of the time of use) or does it charge differently say like during peak hours?

Free online tool to calculate your umeme electricity bills – http://calculator.co.ug/umeme-postpaid-electricity-bill-calculator

Dear Dignited team, Thank you for the article. This is a good insight for all electricity users. The important thing is to determine the apparatus that consumes the highest energy. Energy saving efforts can be directed to that. Often times we focus on switch OFF lights, when the kettle/fridge is the ‘monster’.

Secondly, while the computation is right. It is for Post paid service, NOT YAKA as the headline suggests. I have attached the Yaka billing.

Good service from you.

Thank you.

Hey, thanks for the chart. Quite revealing. Could you explain the cost of discounted first 15 units @ ugx 150 for the subsequent purchases of the month? Are the first 15 units of the month only discounted for the first purchase only and the subsequent purchases are not??

My landlord has one Yaka meter in his house but has some other people on the same yaka but then i have one refrigerator, TV five bulbs (energy savers) and music system but these are only used during the evening hours.

How come i’m charged 140562sh per month and yet others pay ten thousand amonth?

Some free app [My Yaka Bill Calculator] on google play to help you calculate your Yaka bills and estimate how much units you would need based on the appliances you use – https://goo.gl/1jVEYg