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@Mukiha and energy saving bulbs!!!!!!!!!
Rank: Member Joined: 8/16/2012 Posts: 660
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McReggae wrote:@M7, now i understand why you wanted to hide this thread this side!!!!! Daddy Owen wrote:Mbona mbona mbonaaaa..? Live and learn; and don’t forget, nothing ventured, nothing gained.
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Rank: Elder Joined: 2/27/2007 Posts: 2,768
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limanika wrote:Impunity wrote:Sir consider 100W incandescent lamp priced at KES. 40 Now consider a Phillip energy saving bulb priced at KES. 280 and giving an equivalent of 100W of luminescence from an incandescent bulb! I let the bulb shine/wakas for 5 hours per day daily; after how many days will I recoup my investment? As in what is the break even point. Please explain with figures and give examples to make it sink in. Thanks.  Mukiha must be busy elsewhere. Let him review my working below when he comes back. Let us assume you are domestic consumer and your average monthly power bill is KSh. 2,000.00 This bill includes fixed charge of KShs. 120/-. Hence, balance or real cost of power units (Kilowatt hours) is KShs. 2000-120 = 1880/- The tariff for domestic consumers is structured as follows: Charge of KShs. 2/- for the first 1-50 units Charges of KShs 8.10 for the next 51-1500 units Hence, number of units consumed in an average month can be given by: (1880- (2*50) /8.10) + 50 = 270 units The average cost per unit is therefore given by KShs. 2000/270= KShs. 7.40 Assume you went ahead to buy the incandescent bulb. The number of units at the end of the month attributable to the bulb is given by: 0.1*5*30=15kwh Hence this bulb will cost you 15*7.4 = KShs. 104.00 in power bills for one month. Assuming you alternatively went for equivalent energy saving bulb of 18watts, the number of units consumed at the end of the month attributable to the energy saving bulb is: .018*5*30 = 2.7kwh Hence the energy saver will cost you 2.7*7.4 = KShs. 20/- in power bills for one month. The difference in cost of energy for the two options is Ksh. 104-20 = Ksh. 84/- The difference in initial purchase cost is Khs. 280-40 = 240/- Hence, it will take you 240/84 = 2.8 months to recover the additional cost of buying energy saver bulb. But remember the lifespan of energy saving bulbs is many times more that of incandescent bulb. @ limanika A nice trial, but the concept is wrong...the reasoning is wrong...the mathematical calculations are accurate. You don't calculate the electrical power (energy) consumed by a devise or an appliance starting with the amount that appears on the bill or that you would wish to spend... ...besides, the presence of a safe alone does not signify that there is money inside...
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Rank: Member Joined: 8/16/2012 Posts: 660
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Kaigangio wrote:limanika wrote:Impunity wrote:Sir consider 100W incandescent lamp priced at KES. 40 Now consider a Phillip energy saving bulb priced at KES. 280 and giving an equivalent of 100W of luminescence from an incandescent bulb! I let the bulb shine/wakas for 5 hours per day daily; after how many days will I recoup my investment? As in what is the break even point. Please explain with figures and give examples to make it sink in. Thanks. Mukiha must be busy elsewhere. Let him review my working below when he comes back. Let us assume you are domestic consumer and your average monthly power bill is KSh. 2,000.00 This bill includes fixed charge of KShs. 120/-. Hence, balance or real cost of power units (Kilowatt hours) is KShs. 2000-120 = 1880/- The tariff for domestic consumers is structured as follows: Charge of KShs. 2/- for the first 1-50 units Charges of KShs 8.10 for the next 51-1500 units Hence, number of units consumed in an average month can be given by: (1880- (2*50) /8.10) + 50 = 270 units The average cost per unit is therefore given by KShs. 2000/270= KShs. 7.40 Assume you went ahead to buy the incandescent bulb. The number of units at the end of the month attributable to the bulb is given by: 0.1*5*30=15kwh Hence this bulb will cost you 15*7.4 = KShs. 104.00 in power bills for one month. Assuming you alternatively went for equivalent energy saving bulb of 18watts, the number of units consumed at the end of the month attributable to the energy saving bulb is: .018*5*30 = 2.7kwh Hence the energy saver will cost you 2.7*7.4 = KShs. 20/- in power bills for one month. The difference in cost of energy for the two options is Ksh. 104-20 = Ksh. 84/- The difference in initial purchase cost is Khs. 280-40 = 240/- Hence, it will take you 240/84 = 2.8 months to recover the additional cost of buying energy saver bulb. But remember the lifespan of energy saving bulbs is many times more that of incandescent bulb. @ limanika A nice trial, but the concept is wrong...the reasoning is wrong...the mathematical calculations are accurate. You don't calculate the electrical power (energy) consumed by a devise or an appliance starting with the amount that appears on the bill or that you would wish to spend... @Kaigangio Apart from just the small error of 15*7.4=111, Everything just Ok Since the bill amount was used for the purpose of calculating average cost of one (1) kwh Live and learn; and don’t forget, nothing ventured, nothing gained.
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Rank: Veteran Joined: 9/21/2011 Posts: 2,032
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Kaigangio wrote:limanika wrote:Impunity wrote:Sir consider 100W incandescent lamp priced at KES. 40 Now consider a Phillip energy saving bulb priced at KES. 280 and giving an equivalent of 100W of luminescence from an incandescent bulb! I let the bulb shine/wakas for 5 hours per day daily; after how many days will I recoup my investment? As in what is the break even point. Please explain with figures and give examples to make it sink in. Thanks. Mukiha must be busy elsewhere. Let him review my working below when he comes back. Let us assume you are domestic consumer and your average monthly power bill is KSh. 2,000.00 This bill includes fixed charge of KShs. 120/-. Hence, balance or real cost of power units (Kilowatt hours) is KShs. 2000-120 = 1880/- The tariff for domestic consumers is structured as follows: Charge of KShs. 2/- for the first 1-50 units Charges of KShs 8.10 for the next 51-1500 units Hence, number of units consumed in an average month can be given by: (1880- (2*50) /8.10) + 50 = 270 units The average cost per unit is therefore given by KShs. 2000/270= KShs. 7.40 Assume you went ahead to buy the incandescent bulb. The number of units at the end of the month attributable to the bulb is given by: 0.1*5*30=15kwh Hence this bulb will cost you 15*7.4 = KShs. 104.00 in power bills for one month. Assuming you alternatively went for equivalent energy saving bulb of 18watts, the number of units consumed at the end of the month attributable to the energy saving bulb is: .018*5*30 = 2.7kwh Hence the energy saver will cost you 2.7*7.4 = KShs. 20/- in power bills for one month. The difference in cost of energy for the two options is Ksh. 104-20 = Ksh. 84/- The difference in initial purchase cost is Khs. 280-40 = 240/- Hence, it will take you 240/84 = 2.8 months to recover the additional cost of buying energy saver bulb. But remember the lifespan of energy saving bulbs is many times more that of incandescent bulb. @ limanika A nice trial, but the concept is wrong...the reasoning is wrong...the mathematical calculations are accurate. You don't calculate the electrical power (energy) consumed by a devise or an appliance starting with the amount that appears on the bill or that you would wish to spend... There are other ‘charges’ that go into the power bill and didn’t have time to separate all that. Mine is more of a rough working - as much as you can do in about 3 minutes without any elec bill to refer to. I however consider the result sufficient for the purpose at hand since this is not an exam and no one is paying for my services. If you have the time you could separate all these other items for us so we can see if there is any major variance.
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Rank: Elder Joined: 2/27/2007 Posts: 2,768
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Museveni wrote:Kaigangio wrote:limanika wrote:Impunity wrote:Sir consider 100W incandescent lamp priced at KES. 40 Now consider a Phillip energy saving bulb priced at KES. 280 and giving an equivalent of 100W of luminescence from an incandescent bulb! I let the bulb shine/wakas for 5 hours per day daily; after how many days will I recoup my investment? As in what is the break even point. Please explain with figures and give examples to make it sink in. Thanks. Mukiha must be busy elsewhere. Let him review my working below when he comes back. Let us assume you are domestic consumer and your average monthly power bill is KSh. 2,000.00 This bill includes fixed charge of KShs. 120/-. Hence, balance or real cost of power units (Kilowatt hours) is KShs. 2000-120 = 1880/- The tariff for domestic consumers is structured as follows: Charge of KShs. 2/- for the first 1-50 units Charges of KShs 8.10 for the next 51-1500 units Hence, number of units consumed in an average month can be given by: (1880- (2*50) /8.10) + 50 = 270 units The average cost per unit is therefore given by KShs. 2000/270= KShs. 7.40 Assume you went ahead to buy the incandescent bulb. The number of units at the end of the month attributable to the bulb is given by: 0.1*5*30=15kwh Hence this bulb will cost you 15*7.4 = KShs. 104.00 in power bills for one month. Assuming you alternatively went for equivalent energy saving bulb of 18watts, the number of units consumed at the end of the month attributable to the energy saving bulb is: .018*5*30 = 2.7kwh Hence the energy saver will cost you 2.7*7.4 = KShs. 20/- in power bills for one month. The difference in cost of energy for the two options is Ksh. 104-20 = Ksh. 84/- The difference in initial purchase cost is Khs. 280-40 = 240/- Hence, it will take you 240/84 = 2.8 months to recover the additional cost of buying energy saver bulb. But remember the lifespan of energy saving bulbs is many times more that of incandescent bulb. @ limanika A nice trial, but the concept is wrong...the reasoning is wrong...the mathematical calculations are accurate. You don't calculate the electrical power (energy) consumed by a devise or an appliance starting with the amount that appears on the bill or that you would wish to spend... @Kaigangio Apart from just the small error of 15*7.4=111, Everything just Ok Since the bill amount was used for the purpose of calculating average cost of one (1) kwh Three things to consider... 1. The bill amounts is composed of lighting load, small power loads (refregerator, iron, water heating etc) and cable losses (though negligible in the short term). Assuming it to be all lighting load is definitely untrue. 2. The quoted power output on the lamp is not exactly the same as the input power due to ballast losses, cathode losses and prevailing power factor of the lamp. So you cannot use indicated power for consumptions computations. 3. The physical status of the lamps do change gradually (rapidly in Nairobi) and as such the initial illumination levels of new lamps will not be used to compute the comparisons of the payback periods accurately due to dust and lamps deterioration. ...besides, the presence of a safe alone does not signify that there is money inside...
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Rank: Veteran Joined: 9/21/2011 Posts: 2,032
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Bigchick wrote:limanika wrote:Impunity wrote:Sir consider 100W incandescent lamp priced at KES. 40 Now consider a Phillip energy saving bulb priced at KES. 280 and giving an equivalent of 100W of luminescence from an incandescent bulb! I let the bulb shine/wakas for 5 hours per day daily; after how many days will I recoup my investment? As in what is the break even point. Please explain with figures and give examples to make it sink in. Thanks. Mukiha must be busy elsewhere. Let him review my working below when he comes back. Let us assume you are domestic consumer and your average monthly power bill is KSh. 2,000.00 This bill includes fixed charge of KShs. 120/-. Hence, balance or real cost of power units (Kilowatt hours) is KShs. 2000-120 = 1880/- The tariff for domestic consumers is structured as follows: Charge of KShs. 2/- for the first 1-50 units Charges of KShs 8.10 for the next 51-1500 units Hence, number of units consumed in an average month can be given by: (1880- (2*50) /8.10) + 50 = 270 unitsm The average cost per unit is therefore given by KShs. 2000/270= KShs. 7.40 Assume you went ahead to buy the incandescent bulb. The number of units at the end of the month attributable to the bulb is given by: 0.1*5*30=15kwh Hence this bulb will cost you 15*7.4 = KShs. 104.00 in power bills for one month. Assuming you alternatively went for equivalent energy saving bulb of 18watts, the number of units consumed at the end of the month attributable to the energy saving bulb is: .018*5*30 = 2.7kwh Hence the energy saver will cost you 2.7*7.4 = KShs. 20/- in power bills for one month. The difference in cost of energy for the two options is Ksh. 104-20 = Ksh. 84/- The difference in initial purchase cost is Khs. 280-40 = 240/- Hence, it will take you 240/84 = 2.8 months to recover the additional cost of buying energy saver bulb. But remember the lifespan of energy saving bulbs is many times more that of incandescent bulb. Wow! Which school did you go to? Did you represent the school in the Zonal Science congress before proceeding to the National. I need 10 bulbs for my house and I can see the savings will be something to think about.Shida ni initial outlay.Will do it in stages.2 per month. Meanwhile please offer the same details for Flouricent tubes. Which School? I thought you will ask University?! Anyway I used basic algebra skills learnt in Class 6 or thereabout!!!!
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Rank: Elder Joined: 6/17/2008 Posts: 23,365 Location: Nairobi
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@Kaigz, with all that taken into consideration, @limanika's analysis gives a clear picture for comparison, unless to put yours down!!!!! ..."Wewe ni mtu mdogo sana....na mwenye amekuandika pia ni mtu mdogo sana!".
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Rank: Elder Joined: 3/2/2009 Posts: 26,325 Location: Masada
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McReggae wrote:Ante_Christa wrote:Names here are not familiar .....  the usual suspects have been left behind.  I told admin!!! For the last 24 hours I have missed this! NKT. Portfolio: Sold
You know you've made it when you get a parking space for your yatcht.
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@Mukiha and energy saving bulbs!!!!!!!!!
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