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R65k to install solar? Need to lower elect bill


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Hallo,

As so many previous threads, I need your advice.

My elect bill is about R4k per month, I need to reduce that and minimize loadshedding.

I only have R65k to do this. I will DIY what I can but need advice.

I was thinking a Sunsynk 5KW inverter and a small battery for starters. Something like this:

https://powerforum-store.co.za/collections/batterys/products/pylon-us2000b-plus-2-4kwh-li-ion-battery-excl-brackets

Budget is now at around R38k.

Is it possible to add panels and get all the cables/mounting/DB board/sundries?

My idea is to run most of my load during the day, when we have sufficient sun and only to use the battery during loadshedding (running only essentials). During night/cloudy days, I will use grid/Eskom. 

I am hoping that the above would save me about R1500 per month on my bill? If it saves me R1500 on the bill, I can spend the money.

 

I have the following:

- 2x 200litre electrical geysers

- 1x Stove

- 1x 750kw swimming pool

- 2x Front loader washing machines

- 1x Dishwasher

- 1x 1.1kw borehole

- 1x Electric fence

- 4x fridges

Only using LED lighting and I do not have any power monitoring. I take a picture of the electricity meter daily at 06h00 and I see the most I have used during a day is 45 units. The least is around 17 units. We do not use the stove/oven since we have a airfryer and a deepfryer. I know I need to reduce my daily consumption but spending R7k for a gas geyser (times two), leaves me with R51k. Adding electricity monitoring, reduces my budget even more. 

What do you suggest? 

Edited by McGuywer
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Gas is great when you use very little water. It also works great as a backup when you heat your geyser with solar PV and need to instantly boost the temps. Gas will not save you money if you need to heat lots of water. 

If you need a lot of hot water a heatpump saves quite a bit and they work well running on a inverter as they draw very little power. 

If you want to heat 2 geysers on solar PV you are looking at 10+ panels at least. You always need more panels than you think you need, trust me. I bought 4 extra and I still want more

Solar is quite an expensive excercise, and you are never done, after round one you are adding more panels and optimising, getting more batteries etc. . Batteries are nice to have for loadshedding but kills the ROI of any investment. 5KWh of battery will cost you about R30K and they only store R3 * 5KWh = R15 of electricity if you cycle it from 100 to 0% per day. That is enough to keep the lights on during loadshedding

If you have the sunshine and roof pointing to North  (Or East West) and enough space. Finance the project similar to what you would do with a car and do it properly.

Solar will likely only pay for itself in 8-12 years. Also do not use the best case scenario to calculate your savings

 

 

 

 

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Personal opinion. Layman's 2c, consider at own risk.

I'd go the route of NOT investing in the battery yet, but maximising the amount of panels you can get.

Problem is, if you have basically just the inverter and the battery, that's not saving you any money, you save money when you start to generate power.

The idea to get a 2.4kWh Pylontech will probably leave you frustrated, because that battery by itself can only deliver 1.2kW of power. A few lights, maybe the fridges, but soon after that it ends  and your 5kW inverter will feel like it's driving Miss Daisy.

Personal take, get as close to 5kW of panels as you can with the 5kW Sunsynk inverter. The 5kW solar will not eliminate all your usage, but mostly eliminate the consumption that you are paying for at the highest level of the inclining block tariffs, so the effective returns are highest, and investing more will yield diminishing returns. Use the savings after a while to finance some bigger batteries.

Other than that, some basics like geyser timers and geyser blankets may help, as may a pool cover and reviewing the amount of filtration your pool needs. Twice daily turnover with a pool cover could possibly be enough.

 

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McGuywer,

my take for what it is worth...

your mission statement is to reduce your electricity bill, focused which is great.

Get either the solar water heater or heat pump. That right there as a rule of thumb about 20% saving on your current bill.

Though not popular.... (I have my helmet on for the stones that may be lobbed my way!).... buy a petrol generator and if the budget allowed a diesel generator. This will get you past the load shedding hump in the short term. I can tell you that even with over 30kW of battery storage, Eskom has pushed my little system and after a week of continued load shedding I have had to run the little gennie during load shedding to give the solar time to fully recharge itself. Granted my panels have lagged behind my battery capacity but roof space is also limited.

Get the largest capacity inverter you can afford, a 3kW is nice but small if you intend to make a dent in your eskom bill. Add your solar panels and batteries as the budget allows. You will most likely run out of roof real estate long before the budget is exhausted!  Batteries will be your albatross,l but an investment worth making if you cycle the batteries everyday and do so agressively. I actually started with a single 2.4kWh pylontech and it would be flat every night by 10-11pm! Budget limitations meant that I change my approach to increasing capacity, so I started down the DIY path and started building my own batteries.

Enjoy the journey it will be very exciting.

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Forget batteries, way too expensive and with your load you'll deplete them in no time a few times a day.. 

Solar panels and a large inverter, but then a large inverter say 10kw is around your entire budget.. this excludes panels, mounting, wiring, installation etc.

  • Make 100% sure both your geysers are wrapped up in blankets and set to around 50 degrees or so, you can tweak it. Geysers account for around 60% of electricity usage. Maybe look at retrofitting your geyser to be solar, that is glass tubes on the roof, they work amazingly well. I just read a 200L electric geyser uses 14kwh per day on a household of 4 people. So you're using 28kwh a day = R56 give or take a day or R1680 per month to heat those puppies. Now you can't get that to zero, but you could chop that down by half at least with tubes.
  • 750w pool motor, its winter so you can literally run it once a week for an hour to turn the water over. Summer depending on your pool size, once a day for an hour is fine.
  • 1.1kw borehole, not sure if that is your drinking water or how often you use it to water the garden.
  • Do you really need 4 fridges? Each fridge can consume between 150w-500w each depending on size. Maybe look at selling the 4 fridges and buying 1 or 2 inverter energy efficient fridges.
  • 2x front loading washing machines, all depends on how often you use them and if they are also tumble dryers? If so, they chow through electricity like an Ethiopian cow at a buffet, that and they are never that great. 

I know load shedding is a pain in the rear end, but what are you wanting to achieve during the load shedding? If it's just to watch some tv and use the internet at night then I would also look at a small trolley type inverter or a fancy lithium battery pack, they are the same just more expensive. That covers load shedding and tv watching for a few hours until the power comes on. I have a little camping 150w inverter and a small 40ah battery, I made a little box and that powers my fibre internet during load shedding, I then just play on my phone, cost like R1500 and I've used it for years.

Food for thought :) 

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Posted (edited)

Your have a tight budget but workable if you choose a different Inverter. Have a look at Luxpower SNA5000 at R12k, Pylontech UP5000 for loadshedding at R27k

https://www.inverter-warehouse.co.za/products/solar-select-lux-power-sna5000

https://www.inverter-warehouse.co.za/products/pylontech-lithium-ion-4-8kw-up5000-battery

Change your geysers heating elements to Geyser wise PTC elements, get the 2Kw ones at +-R5k for two, and use timers to switch them on and OFF. Then get ten PV panels @ R23k 

https://www.inverter-warehouse.co.za/products/jinko-solar-panel-tiger-395w-mono-facial

You will be slightly over budget but you can get eight panels and still achieve what you are looking for, both reduction in your bill and the battery will be enough for loadshedding 🙂

Then you can expand when funds allow, by getting a second Luxpower inverter to get 10Kw, a second battery to get 10Kwh and more panels if you have enough roof space. 

Do not worry about getting a sunsynk if you have limited funds, there is cheaper inverters that can do the job. Another cheapie to consider is Growatt SPF5000ES

 

Edited by hoohloc
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Posted (edited)

Ive done a DIY job at home so no expert, but personally I'd do exactly as you've stated -

1. Decent inverter (Sunsynk) to see you through many years. Can parallel a 2nd inverter later if needs be. 

2. Small (expandable) battery running pure essentials until you can afford bigger batteries (you'll need to split DB accordingly).

3. Whatever number of panels you can afford (plan properly for future panel expansion). 

You'll start saving from the get go. 

Every 2nd month, take the savings and buy an additional panel - planned properly it'll be pure plug n play onto your existing array.

Start increasing battery banks once you have enough panels to produce for decent battery storage. At this point you can start adding some extra loads to the essentials bus. 

What the guys say about solar water heaters and heat pumps is very true! Should plan that into your system for sure. Whether you do that first or PV first- personal preferende 😉

Hey presto, a few years down the line you're saving 3.5k per month without an exhorbitant initial investment;-)

Edited by markus_m2
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Posted (edited)

My starting point would be totally removed from most solutions we see here. The easiest highest return on investment is not Alway using the best around. We tend to look at storage due to LS as the 1st prize.

Based on the main requirement and due to the ability to change loads for daytime a grid tied just makes sense.

No need to split DB. 1 circuit breaker to supply power for the inverter to generate and feed back to all loads.

Solis 5G or S6 in 4.6kw. You can use over 5kw in panels as it will just throttle at 4.6kw. With more panels you get more PV early and later in the day. Cost R12 000.

10 x 480W mono panels in stock cost R28000. Winter generation 19.2kwh per day. Summer average 24kwh per day. Yes you don't have back up but a 1600W pure sine trolley with batteries you can get for R8000 at geewiz. This can help to run 1 fridge/freezer during longer outage running it say 30min on and 30 off.

Average yield during the year in Gauteng 22kwh per day. 660kwh per month. At a cost per unit of R2.50 the saving is R1650 per month.

When the load is over what the inverter can produce from PV you just get from the grid.

Easy to install. To make it legal with COC and engineer to sign off R6000.

What is left in the budget buys all the DC sundries. Sit back and enjoy the savings. No cost towards fitting other elements. If a heat pump is added it goes over budget but will be money well spent to heat water at 33-50% of the cost of a normal element. All day time power is from PV.

Suggested system will pay itself in about 30 months.

Why no battery in my main suggesting. A 270W panel generates 1kwh per day at about R1600. Using a lithium battery costs R5000 to store 1kwh for use when needed.

 

Edited by Scorp007
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On 2022/07/02 at 8:14 AM, Rch1 said:

Maybe look at retrofitting your geyser to be solar, that is glass tubes on the roof, they work amazingly well. I just read a 200L electric geyser uses 14kwh per day on a household of 4 people. So you're using 28kwh a day = R56 give or take a day or R1680 per month to heat those puppies. Now you can't get that to zero, but you could chop that down by half at least with tubes.

Retrofit solar geyser kit alone saved and paid back the quickest for me.  The extra cash you invest in getting an even better inverter 8kw and add panels as the money comes in as people are suggesting.  Sunsynk will work without batteries and this you can expand battery bank last.

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Hi McGuywer

Good comments in this forum.

FYI, I converted my home to solar @ R90k bringing my bill down from what would be with today's Eskom tariffs R1800pm to less than R200pm.

You want to bring down your peak consumption so that you can run more concurrent devices with the least PV installed. E.g. I replaced my 3kw kettle with a 1.4kw one. Make sure the fridge/freezer Tetrafluoroethane is topped up to ensure fridge does not run 24/7 but only a third thereof. As said in this forum, get geyser blankets but also isolate the pipes.

I suggest the hybrid inverter and I personally would add the 2.4 kw battery. I found that my bill reduced R200 to R300 per month moving from a gridtie inverter to hybrid. The battery handles peaks that would come from Eskom and dips in utility are stored for later consumption. The benefit is also critical loads work when load shedding.

The forum is correct that rather spend on PV panels to save money and get a faster ROI.

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On 2022/06/30 at 8:47 PM, McGuywer said:

Hallo,

As so many previous threads, I need your advice.

My elect bill is about R4k per month, I need to reduce that and minimize loadshedding.

I only have R65k to do this. I will DIY what I can but need advice.

I was thinking a Sunsynk 5KW inverter and a small battery for starters. Something like this:

https://powerforum-store.co.za/collections/batterys/products/pylon-us2000b-plus-2-4kwh-li-ion-battery-excl-brackets

Budget is now at around R38k.

Is it possible to add panels and get all the cables/mounting/DB board/sundries?

My idea is to run most of my load during the day, when we have sufficient sun and only to use the battery during loadshedding (running only essentials). During night/cloudy days, I will use grid/Eskom. 

I am hoping that the above would save me about R1500 per month on my bill? If it saves me R1500 on the bill, I can spend the money.

 

I have the following:

- 2x 200litre electrical geysers

- 1x Stove

- 1x 750kw swimming pool

- 2x Front loader washing machines

- 1x Dishwasher

- 1x 1.1kw borehole

- 1x Electric fence

- 4x fridges

Only using LED lighting and I do not have any power monitoring. I take a picture of the electricity meter daily at 06h00 and I see the most I have used during a day is 45 units. The least is around 17 units. We do not use the stove/oven since we have a airfryer and a deepfryer. I know I need to reduce my daily consumption but spending R7k for a gas geyser (times two), leaves me with R51k. Adding electricity monitoring, reduces my budget even more. 

What do you suggest? 

I tend to agree with @Mad Mike on the water heating.

I reduced my bill by close to 45% at first just by having gas installed for the hobs and having EV tube conversion performed on the geyser.

^ these two combined should be within your budget and you'd still have spare change.

... the benefit of the above is that even during load-shedding you'd still have hot water for showering and you can still make a hot cup of joe.

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On 2022/07/02 at 8:04 PM, Scorp007 said:

My starting point would be totally removed from most solutions we see here. The easiest highest return on investment is not Alway using the best around. We tend to look at storage due to LS as the 1st prize.

Based on the main requirement and due to the ability to change loads for daytime a grid tied just makes sense.

No need to split DB. 1 circuit breaker to supply power for the inverter to generate and feed back to all loads.

Solis 5G or S6 in 4.6kw. You can use over 5kw in panels as it will just throttle at 4.6kw. With more panels you get more PV early and later in the day. Cost R12 000.

10 x 480W mono panels in stock cost R28000. Winter generation 19.2kwh per day. Summer average 24kwh per day. Yes you don't have back up but a 1600W pure sine trolley with batteries you can get for R8000 at geewiz. This can help to run 1 fridge/freezer during longer outage running it say 30min on and 30 off.

Average yield during the year in Gauteng 22kwh per day. 660kwh per month. At a cost per unit of R2.50 the saving is R1650 per month.

When the load is over what the inverter can produce from PV you just get from the grid.

Easy to install. To make it legal with COC and engineer to sign off R6000.

What is left in the budget buys all the DC sundries. Sit back and enjoy the savings. No cost towards fitting other elements. If a heat pump is added it goes over budget but will be money well spent to heat water at 33-50% of the cost of a normal element. All day time power is from PV.

Suggested system will pay itself in about 30 months.

Why no battery in my main suggesting. A 270W panel generates 1kwh per day at about R1600. Using a lithium battery costs R5000 to store 1kwh for use when needed.

 

You could add an 8kw  Sunsynk as a Grid-Tie and cable it in in the same way, will cost a little more than the Solis but would give you the flexibility of installing a battery later (and changing the cabling obviously)

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7 minutes ago, Sc00bs said:

You could add an 8kw  Sunsynk as a Grid-Tie and cable it in in the same way, will cost a little more than the Solis but would give you the flexibility of installing a battery later (and changing the cabling obviously)

I have to fully agree with the 8kw Sunsynk looking at things going forward. With the Solis at over R22th cheaper I just tried to stick within the budget😂😂

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3 minutes ago, Scorp007 said:

I have to fully agree with the 8kw Sunsynk looking at things going forward. With the Solis at over R22th cheaper I just tried to stick within the budget😂😂

Agreed, 5kw Solis would be a best way if the only objective is to reduce the Eskom bill. 

I think @McGuywer needs to decide how important the option of avoiding load shedding is, will cost an extra 20k for the inverter + whatever battery he decides on. 

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Since a Sunken Synk won't run without batteries or the grid, either one or the other has to be there... I'd vote for a high Voltage Axpert type that can generate power without either and plenty of panels, if the aim is firstly to reduce energy payments to the monopoly outfit, get a 5kW or 2 Axpert with boatloads of solar panels and use all the electrons it/they can produce and keep your energy consumption from the grid down at night... eventually add 5+kWh's worth of LFP energy storage to keep the lights and fridges on during night time...

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48 minutes ago, Kalahari Meerkat said:

Since a Sunken Synk won't run without batteries or the grid, either one or the other has to be there... I'd vote for a high Voltage Axpert type that can generate power without either and plenty of panels, if the aim is firstly to reduce energy payments to the monopoly outfit, get a 5kW or 2 Axpert with boatloads of solar panels and use all the electrons it/they can produce and keep your energy consumption from the grid down at night... eventually add 5+kWh's worth of LFP energy storage to keep the lights and fridges on during night time...

Now the Sunsynk can run grid tied with grid and without battery as was suggested earlier. I think this has been suggested a few times by members. You just need either grid or batteries at any stage.

@Sc00bs

A cheaper solution could be a small 1kw Axpert with a Hubble S-120 for the LS times while the Solis saves quite a bit during the day. The small Axpert goes for below R4000.

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On 2022/07/11 at 10:50 PM, RabidBunny said:

I tend to agree with @Mad Mike on the water heating.

I reduced my bill by close to 45% at first just by having gas installed for the hobs and having EV tube conversion performed on the geyser.

I keep getting shot down about new solar installations not thinking about water heating first, but even if you trash your water heating system later it is the most economical start (IMO). Even if you only solar heat one of them and pay a plumber to change some pipes, the geyser heating should be the first to go. And despite many arguing against due to other methods, it is far cheaper than installing an Electrical conversion system (heat pumps etc) to cover that from day 1. Once you get a large solar installation, then by all means change your approach, but solar heating tubes work with almost minimal maintenance and breakdown,

Like every installation each is different and unique. In my case Gas wasn't an option for ovens and stoves due to my wife's business. It would take a very expensive Gas stove to maintain exact temperatures she needed. But gas is a valid alternative if you consider the Gas litres and cost vs your electricity cost. In my personal case the costs were too close to justify the capital expense, so we run the baking oven with Solar Electricity (just can only run the Stove/Oven with no other heating element at the same time due to Invertor limitations, but that is family education).

Government electricity bill, with Solar (Electricity & Water) dropped from R3000/mth in 2015, to current of R600/mth. Despite increases in charges and doing a lot to reduce consumption in lights, education, a few heaters using gas instead +++. It is just learning.

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