Power backup during Kenya power blackouts

I spend lots of time at home and we know how kenya power can frustrate you when you decide t work at home and worse still if it’s those morning to late night, I tried some UPS but they lasted just a few minutes even on the router only, last week I was so frustrated I decided to get a proper backup, so far I have tested it and it’s really impressive. here is what I got



It was alot of money spent when angry and I was afraid it was a waste but a week later I am thrilled and I thought I would share this.
I am powering a ceiling fan, a 43 inch tv, a home theater, zuku router, laptop and 3 lights, total 205 watts which is equal to around 1 amp load, seeing that i got a 200ah battery I can get about 200 hours backup, I have not tested this but it went all the items up from 7am to abut 9 pm yesterday.
The only annoying thing is the inverter has a noisy fan which comes on every 20 minutes when charging but lasts only about 30 seconds, nice setup for home based free lancers.
I am still checking out the setup, if there is an electrical guy you can tell me if I was screwed or got a good deal, when power goes the changeover is instant only a beep comes from the inverter.
can i put the inverter in a drawer the fan is loud and comes on unexpectedly?

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I’m self taught on matters solar/battery. Mine is not professional advice but DIY experience and internet.

I don’t know how you did your math but i know the load is more than 1 amp. A smartphone charger alone draws 2 Amps. Did you include inverter efficiency in the calculations.

You will roast your fan and system too. There is a reason it has a cooling fan. Learn to live with the noise. Batteries work best at 25 degrees Celsius.

You will damage your battery. Recommended depth of discharge is 50% of rated battery capacity. Power =Voltage x current. 12vx200A=2400Wh. You then allowed to use half =1200Wh. From your load setup, 1200/205=5.8 hours. Using the system for more than 6 hours with your load of 205Watts not advisable.

Check the life span of battery under different discharge cycles.
https://www.davisandshirtliff.com/solar/product/706-np200-12l

Thanks I got the amps by using the formula amps= volts/watts I got 1.07 amps using a 0.8 power factor for my inverter, I got the watts from the stickers on the appliances, and our kenya power voltage is 240 volts.
The 2 amps on a phone charger is what it puts out not consumes, a 60 watt tv uses about 0.3 amps, a 2000 watt microwave uses about 10 amps.
Thanks for the battery info did some research and they recommend not discharging below 50 and making sure it well ventilated, I found a good place for the inverter where the noise won’t bother me.
someone recommended i get a battery voltage monitor do I really need it.

It doesn’t work like that, calculating backup time is: (Battery Capacity (Ah) X Battery Voltage X efficiency)/ power consumed.

In your case it’s (200 x 12 x 0.8 (efficiency is around 0.8 in most cases))÷ 205= 9.6 hours.
However, things like laptop do not consume power continuously, hence you should check your laptop’s watt hour to see how much it draws.

It was a good deal.

I envy that setup. Seems like a good power back up plan. It’s really nice.

9 hours is still decent and might be more seeing that not all those items will be on at the same time eg my laptop can push 6 hours when full, the lights can be off during the day and I can watch the tv without the home theater.
Electrical engineers should get their act together they mix the units so much ie. batteries in amp hours, generators in KVAs, solar in watts, UPS are in VAs, Kenya power is in KWhs.

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To my understanding of what I remember, the differences in units is mostly due to efficiency. VA is used to measure apparent power (true + reactive), while watts measures true power.

Reactive power is produced when power passes through capacitors and and inductors. I learned that inductors lag voltage while capacitors lag current. This process drops the total power produced. Hence, we can’t measure all in watts, we have to separate to show the differences.

About KPLC (tukiwa attacho), KWh is used as a way to show how much units of power per hour you consume. just like water metres use 1000 litres for a unit.

What you are familiar with and probably I don’t understand well is bits and bytes… where bits measure internet speed, but are not ideal for measuring memory storage… but you can divide by 8 (i think) to convert between the two.

I hope you get the idea now.

Correction, in capacitors the change in voltage lags behind current while in Inductors, change in current lags behind voltage… sorry

Your setup is drawing almost 20 amps from battery to the inverter and since it’s not recommended (if you want your battery to last) to discharge more than 50%, your battery will last theoritically for 10hrs at that load

I’m considering such a set up in shags. Question, how do you charge the battery? Using the mains electricity or?

The charge controller/inverter above does that. There are many other well known brands which can handle even bigger loads

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Those are solar batteries (by davisandshirtliff)which can also be charged by mains… But I would advise you save for Lithium ion batteries since theoretically they last around ten times more than the lead acid backups. However, they are also around five times more expensive for the same capacity. 200Ah is enough though…

Though sijui any company that sells Li-ion batteries with such capacity in Kenya

Same here. Saw some on Aliexpress but the cost of shipping was steep!

I am using KPLC for always on power, I asked and they told me if I wanted solar for Mombasa I would need 3 panels of 100 watts each to keep the battery charged and to power a TV, radio, 15 lights, phone charging, a decoder and a PC.
I will try getting this for ocha, power there rarely goes of but when it does it can take kenya power upto 2 days to get it back.

Centre for alternative technologies CAT sell all types of solar equipment including lithium ion batteries and they deliver using G4S. Google for contacts

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Share with links please. That will help

https://www.davisandshirtliff.com/shop/index.php?route=product/product&product_id=316&search=vispra+100ah