Newbie to Solar power and very impressed with this Forum

pwven · June 2013

Hi all. I am new to this site and have learned more in the last few days reading on this forum than a couple of weeks trying to understand Solar power. I want to install a Solar Power system at my house and will be needing you help to do so.
Piet

Cariboocoot · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Welcome to the forum Piet.

Help is what we're here for.
(Insert joke about some of us needing it here.)

Living in South Africa will present something of a challenge in system design as most of our expertise is centered around North American electrical systems/code. But that doesn't mean it can't be done!

niel · June 2013

Re: Newbie to Solar power and very impressed with this Forum

you get a welcome from me too and some have said i'm beyond help.:p see i forgot the smiley face or i might misinterpret myself and get mad.

anyway, other challenges exist such as what equipment is available there or if you can have said solar equipment shipped into the country and what kinds of costs are involved. it's difficult to do from that standpoint as we can't say much in that way, but you can read the generalities of how things go. specifics may need to be researched by you for the same reasons and then you can run it past us with the proposed equipment and the specs for it all.

solar_dave · June 2013

Re: Newbie to Solar power and very impressed with this Forum

The first step is understanding your goals. You need off grid power or will you Grid tie? Is it for cost reduction, green or unreliable utility?

westbranch · June 2013

Re: Newbie to Solar power and very impressed with this Forum

I have a suspicion that the MN Classics are available from a comment by boB about one of the turbine manufacturers, Kestrel using the CL....
Nothing on their Internat. list of dealers though

Yup, found the page showing a CL200 (recommended?) on page 2
http://www.kestrelwind.co.za/assets/wind%20turbines/kestrel%20e400n.pdf

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Cariboocoot wrote: »

Welcome to the forum Piet.

Help is what we're here for.
(Insert joke about some of us needing it here.)

Living in South Africa will present something of a challenge in system design as most of our expertise is centered around North American electrical systems/code. But that doesn't mean it can't be done!

Hi Cariboocoot. I do not think it will that big a challenge to put together a good system, as the basic technical stuff is about the same. The sun, temperature and sunshine hours are different and I have started to get some of that info already.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

niel wrote: »

you get a welcome from me too and some have said i'm beyond help.:p see i forgot the smiley face or i might misinterpret myself and get mad.

anyway, other challenges exist such as what equipment is available there or if you can have said solar equipment shipped into the country and what kinds of costs are involved. it's difficult to do from that standpoint as we can't say much in that way, but you can read the generalities of how things go. specifics may need to be researched by you for the same reasons and then you can run it past us with the proposed equipment and the specs for it all.

Hi Niel. Thanks for the welcome. I think that most of the stuff I will get locally, ether local manufacture or imported.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

solar_dave wrote: »

The first step is understanding your goals. You need off grid power or will you Grid tie? Is it for cost reduction, green or unreliable utility?

Hi solar_dave. I want to install an off the grid system and the main reasons being to reduce my electricity costs and save more by not getting the yearly increases.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

westbranch wrote: »

I have a suspicion that the MN Classics are available from a comment by boB about one of the turbine manufacturers, Kestrel using the CL....
Nothing on their Internat. list of dealers though

Yup, found the page showing a CL200 (recommended?) on page 2
http://www.kestrelwind.co.za/assets/wind%20turbines/kestrel%20e400n.pdf

Hi westbranch. Thanks for the link, there are some interesting information there.

solar_dave · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

Hi solar_dave. I want to install an off the grid system and the main reasons being to reduce my electricity costs and save more by not getting the yearly increases.

If those are your goals and your utility is reliable then consider grid tie, Lots more bang for the buck there. Of course your utility has to support net metering to make that work. I would check that option out first as you should be able to do twice as much solar for the same money as with a battery based off grid system. The other advantage to grid tie is you get credit for 100% of the production, on a battery based off grid system you have some pretty high loses charging the battery bank back up. Then there is the costs of battery, charge controller and inverter with a battery system. Grid tie has one set of electronics, the inverter to sync to your grid connection.

Just a thought as that lines up with your goals.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

I am basically looking to replace about 70% of the grid power with off the grid Solar Power based on the following;
For about 6 months of the year my daily power consumption is 16.5 Kwh per day averaged over a month and this is the amount of power I want to generate. These 6 months are mainly spring and autumn.
The other 6 months are winter and summer when additional power is needed to run air conditioners for cooling and or heating. During this period the power usage is more than 20Kwh per day and I want to leave this extra power usage on the grid so that in summer and winter time I will have a small extra electricity account.
Do this make sense ? or do I have it all wrong?

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

solar_dave wrote: »

If those are your goals and your utility is reliable then consider grid tie, Lots more bang for the buck there. Of course your utility has to support net metering to make that work. I would check that option out first as you should be able to do twice as much solar for the same money as with a battery based off grid system. The other advantage to grid tie is you get credit for 100% of the production, on a battery based off grid system you have some pretty high loses charging the battery bank back up. Then there is the costs of battery, charge controller and inverter with a battery system. Grid tie has one set of electronics, the inverter to sync to your grid connection.

Just a thought as that lines up with your goals.

Thanks for that info. I think the local municipality is nor really in favor of the grid tie system but will follow it up anyway. Have just posted what I have in mind to do.

Photowhit · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

... I want to install an off the grid system and the main reasons being to reduce my electricity costs and save more by not getting the yearly increases.

So long as you understand that in the long run it is very unlikely your solar energy will save you money, when you average out the system costs, we can continue.

You are looking for a large system, Do you know your solar isolation in your area, the potential in South Africa looks good. I didn't hunt but if you have no assistance from the grid you will also need to know your peak use during the times you'll be off grid and the minimal solar isolation for your area during this time, in order to figure out the size inverter you'll need and the size battery bank.

Just a quick "guess" is you'll need a 4-5Kw array, likely a 4000 watt inverter of the correct output and a good size battery bank of 20 - 40 Kw hours storage.

In general solar tends to be expensive compared to grid electric, so plan carefully.

solar_dave · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

I am basically looking to replace about 70% of the grid power with off the grid Solar Power based on the following;
For about 6 months of the year my daily power consumption is 16.5 Kwh per day averaged over a month and this is the amount of power I want to generate. These 6 months are mainly spring and autumn.
The other 6 months are winter and summer when additional power is needed to run air conditioners for cooling and or heating. During this period the power usage is more than 20Kwh per day and I want to leave this extra power usage on the grid so that in summer and winter time I will have a small extra electricity account.
Do this make sense ? or do I have it all wrong?

Well off grid power is about double the cost of grid tie per kWh. What do you pay today per kWh, then you can figure out how long the payback will be to get even on any system.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

solar_dave wrote: »

Well off grid power is about double the cost of grid tie per kWh. What do you pay today per kWh, then you can figure out how long the payback will be to get even on any system.

I can only work out the payback period after I have a budget price of the system but my guess at this stage is about 10 years.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Photowhit wrote: »

So long as you understand that in the long run it is very unlikely your solar energy will save you money, when you average out the system costs, we can continue.

You are looking for a large system, Do you know your solar isolation in your area, the potential in South Africa looks good. I didn't hunt but if you have no assistance from the grid you will also need to know your peak use during the times you'll be off grid and the minimal solar isolation for your area during this time, in order to figure out the size inverter you'll need and the size battery bank.

Just a quick "guess" is you'll need a 4-5Kw array, likely a 4000 watt inverter of the correct output and a good size battery bank of 20 - 40 Kw hours storage.

In general solar tends to be expensive compared to grid electric, so plan carefully.

Hi Photowhit. Here is another link with more detail on solar date for where I stay. http://www.gaisma.com/en/location/kimberley.html

solar_dave · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

I can only work out the payback period after I have a budget price of the system but my guess at this stage is about 10 years.

Just remember that off grid batteries will need to be replaced at some point and require lots of care and feeding. Most new off grid users toast a set of batteries pretty quickly from deficit charging, lack of watering or just over discharging. The system needs to have a real balance and when the weather is such that the batteries don't get the charging they need, a replacement source of charging is required, like the grid or a generator to keep them healthy. Battery maintenance is nasty and fussy too. Taking Specific gravity readings in all that acid is just nasty.

Those are some of the reasons I am a proponent of grid tie when it makes sense. You get much more bang for the money spent and grid tie is pretty much fire and forget. The grid in effect becomes an unlimited battery with long term storage and none of the down sides of actually owning a battery. Of course all that depends on the utility supporting net metering and having a reliable grid.

Photowhit · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

I can only work out the payback period after I have a budget price of the system but my guess at this stage is about 10 years.

I'm surprised you can 'see' a payback date!

I have an off grid system just going on line (or should that be off line) and I live in a nation where electric is relatively cheap and I have no payback date unless electric goes up 50% or more. That's with electric costing about 19 cents a Kwh. My system, home built by others, at current pricing would cost $3-5000 more, I've found good deals and pieced together things. If just installed by a contractor it would likely cost $20K+ and cost around 60 cents a Kwh projected over 30 year life. perhaps more if contractors would be used to replace electronics and battery.

In figuring costs, I figured replacing the forklift battery every 15 years and electronics every 10 years. Something to consider. Only large 2 volt cells have a projected life out 15 years. These may be the most cost effective for long term use.

jzchen · June 2013

Re: Newbie to Solar power and very impressed with this Forum

I don't think the OPs intent is for an off grid system. His intent seems to be to cover his lowest use situation, and then supplement with grid power. He wants to generate the 16.5 kWh per day, and then take the remainder that he needs from the grid. He isn't accounting for his maximum use situation, which he mentions as over 20kWh per day. This extra he intends to take from the grid. I think terminology may be mixed up. An off grid system for the 16.5kWh will fail when he needs the extra energy. No batteries will be necessary as long as the local energy agency allows interconnect.

Photowhit · June 2013

Re: Newbie to Solar power and very impressed with this Forum

jzchen wrote: »

I don't think the OPs intent is for an off grid system. ....

In post #12 the OP states "...I think the local municipality is nor really in favor of the grid tie system but will follow it up anyway. ..."

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

jzchen wrote: »

I don't think the OPs intent is for an off grid system. His intent seems to be to cover his lowest use situation, and then supplement with grid power. He wants to generate the 16.5 kWh per day, and then take the remainder that he needs from the grid. He isn't accounting for his maximum use situation, which he mentions as over 20kWh per day. This extra he intends to take from the grid. I think terminology may be mixed up. An off grid system for the 16.5kWh will fail when he needs the extra energy. No batteries will be necessary as long as the local energy agency allows interconnect.

Hi jzchen. Let me try and put it in another way. (English is not my mother tongue language) Lets say that from December to February (our summer months) I use 25kwh per day and the extra power above 16.5Kwk is used for airconditioners. During this time I want to use 16.5Kwh from the Solar power system and the rest (8.5Kwh) from the grid. March to May the usage will be 16.5 all taken from the Solar system and nothing from the grid. June to August is our winter months and again the extra usage is for heating, 16.5Kwh from the Solar system and 8.5 from the grid. August to November the power usage is back to 16.5Kwh.
The reasons I want to install a off the grid Solar power system is to save on electricity costs, and have a more reliable power supply than the grid in our area. There is a power supply shortage at times and the power is cut off without notice. Hope this is more clear now.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Photowhit wrote: »

I'm surprised you can 'see' a payback date!

I have an off grid system just going on line (or should that be off line) and I live in a nation where electric is relatively cheap and I have no payback date unless electric goes up 50% or more. That's with electric costing about 19 cents a Kwh. My system, home built by others, at current pricing would cost $3-5000 more, I've found good deals and pieced together things. If just installed by a contractor it would likely cost $20K+ and cost around 60 cents a Kwh projected over 30 year life. perhaps more if contractors would be used to replace electronics and battery.

In figuring costs, I figured replacing the forklift battery every 15 years and electronics every 10 years. Something to consider. Only large 2 volt cells have a projected life out 15 years. These may be the most cost effective for long term use.

Below are some cost estimates and the payback showing the payback not taking into account any interst

Year Kwh/Mth R/Mth R/year Accum
1.62 495 801.90 9623 9331
1 1.94 495 962.28 11547 21170
2 2.33 495 1154.74 13857 35027
3 2.80 495 1385.68 16628 51655
4 3.36 495 1662.82 19954 71609
5 4.03 495 1995.38 23945 95554
6 4.43 495 2194.92 26339 121893
7 4.88 495 2414.41 28973 150866
8 5.37 495 2655.86 31870 182736
9 5.90 495 2921.44 35057 217793
10 6.49 495 3213.59 38563 256356

Year 1 to 5 increase = 20%
Year 6 to 10 increase = 10%

The 1.62 R per Kwh is what we are paying at present and that is going up to R1.94 as from next month.
At this stage I estimate that the cost to install a Solar power system to be about R140000.00.
The exchange rate is 10 Rand to 1 USD.

Power is not cheep in the area I stay.

Photowhit · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Hard to tell from your numbers, but at 1:10 I guess your talking @$14,000 for a system, what size system can you get for that? Will this include batteries? what type and size?

20 cents a Kwh isn't ungodly expensive. Since you have so much 'sun' I won't say your numbers are wrong, but I need more data to work with.

Is your expected 'payback' your estimate or an installers?

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Sorry about the data table. I copied it from an worksheet and then this program lumped everything together.
The $14'000 for the system at this stage is only a guess and that must include the batteries. Will post the battery info that I am looking at tomorrow.

westbranch · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Pwven, I do not recall any statements about overall conservation, or energy efficiency so far, IIRC.
Things such as power monitoring to look for places to reduce consumption, such as standard lighting to LED or a newer high efficiency refrigerator, or adding insulation to lower A/C power usage.

jzchen · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

Hi jzchen. Let me try and put it in another way. (English is not my mother tongue language) Lets say that from December to February (our summer months) I use 25kwh per day and the extra power above 16.5Kwk is used for airconditioners. During this time I want to use 16.5Kwh from the Solar power system and the rest (8.5Kwh) from the grid. March to May the usage will be 16.5 all taken from the Solar system and nothing from the grid. June to August is our winter months and again the extra usage is for heating, 16.5Kwh from the Solar system and 8.5 from the grid. August to November the power usage is back to 16.5Kwh.
The reasons I want to install a off the grid Solar power system is to save on electricity costs, and have a more reliable power supply than the grid in our area. There is a power supply shortage at times and the power is cut off without notice. Hope this is more clear now.

Okay, I understand what you want to do. As people already warned batteries are expensive, at least here in the USA. The installer I worked with didn't even recommend it to me even though they would earn a lot of money selling it to me. The battery system addition was an estimated $15000, just off the top of their head.

Off grid usually means you are independent of the grid, meaning no more electricity from the electric company. Now the situation you are stating is that you would like to remove the lowest use situation, and also have power when the grid is down. This is tricky as you would need to supply your whole needs, including during time when power is cut off. If you are okay with power being cut off without notice then you do not need the batteries. If not, then you do, and have to figure out what size would be appropriate for your needs. It may not be necessary to power the whole 25 kWh in an emergency situation like that.

Ideally you would want grid interconnection, which is an on grid system. Just in case you produce more than you use the extra energy would go back to the grid and give you some sort of credit with the electric company...

jzchen · June 2013

Re: Newbie to Solar power and very impressed with this Forum

pwven wrote: »

Below are some cost estimates and the payback showing the payback not taking into account any interst

Year Kwh/Mth R/Mth R/year Accum
1.62 495 801.90 9623 9331
1 1.94 495 962.28 11547 21170
2 2.33 495 1154.74 13857 35027
3 2.80 495 1385.68 16628 51655
4 3.36 495 1662.82 19954 71609
5 4.03 495 1995.38 23945 95554
6 4.43 495 2194.92 26339 121893
7 4.88 495 2414.41 28973 150866
8 5.37 495 2655.86 31870 182736
9 5.90 495 2921.44 35057 217793
10 6.49 495 3213.59 38563 256356

Year 1 to 5 increase = 20%
Year 6 to 10 increase = 10%

The 1.62 R per Kwh is what we are paying at present and that is going up to R1.94 as from next month.
At this stage I estimate that the cost to install a Solar power system to be about R140000.00.
The exchange rate is 10 Rand to 1 USD.

Power is not cheep in the area I stay.

Is that a flat rate on electricity? Here we have a progressive rate. First x kWh art $.13, next y kWh at $.19, and up. Our house hit tier 4, which is $.32 per kWh. Removing the most costly electricity used is what a lot of people are doing here...

The cost of our system after available incentives is about $36744, but may cover our complete usage, (it may be oversized for maximum benefit.)

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

jzchen wrote: »

Is that a flat rate on electricity? Here we have a progressive rate. First x kWh art $.13, next y kWh at $.19, and up. Our house hit tier 4, which is $.32 per kWh. Removing the most costly electricity used is what a lot of people are doing here...

The cost of our system after available incentives is about $36744, but may cover our complete usage, (it may be oversized for maximum benefit.)

We also have a progressive rate and with my usage I am on the top scale already. You have a big system going, hope it works well for you.

pwven · June 2013

Re: Newbie to Solar power and very impressed with this Forum

westbranch wrote: »

Pwven, I do not recall any statements about overall conservation, or energy efficiency so far, IIRC.
Things such as power monitoring to look for places to reduce consumption, such as standard lighting to LED or a newer high efficiency refrigerator, or adding insulation to lower A/C power usage.

Hi westbranch. Have been lowering my power usage by about 25% over the last year by doing the following. All the lights in the house are now LED lights. Have installed a gas stove with gas oven that is now used 95% of the time. Have replaced the normal 3KW geyser with a 1.1KW heat pump for water heating and have efficiency refrigerator and freezer.

stephendv · June 2013

Re: Newbie to Solar power and very impressed with this Forum

Hi Piet,

Welcome to the forum, I'm an ex-pat saffer from Bloemfontein

Regarding your system, I think a semi-off-grid solar setup is a good bet because your usage co-incides well with solar irradiance.

It'll be good to know how long the power outtages are, because if you have the grid available most of the time then it will be much cheaper to buy batteries that just cover 1 day's use. Usually those of us who are pure off-grid will size the battery bank to last for 2-3 days before we have to turn the generator on. This increases the cost of the install considerably.

In Spain the price of electricity continues to rise and it's becoming quite popular to install semi-off-grid systems where the battery bank is cycled daily and is sized for just 1 day's power. Any deficit is then made up for with the grid. I highly recommend forklift batteries because they're the cheapest over their lifetime, i.e. the cost/kWh/year is the lowest of most batteries. And you're likely to find a source of forklift batts locally. The disadvantage of the forklifts is that they come in a single big metal container, which could weight up to 1 ton and it's difficult to remove the individual 2V cells, so you really need to be able to drive up to the place where you want to install them and then have a crane or forklift to unload and install them. But they're very tough batteries and are usually rated at 1200 - 1500 cycles at a depth of discharge of 80%.

You should be able to find chinese solar panels for around R10/Watt, and possibly cheaper if you can go directly to a distributor. In terms of inverters, I think SMA (Sunny Island) are sold there and possibly Victron, both good quality units.

The heat pump + geyser (hot water tank for US folk), is interesting because it'll let you time shift the usage. I.e. only turn on the heat pump when the sun is shining, which means you can go with a smaller battery bank.

Photowhit · June 2013

Re: Newbie to Solar power and very impressed with this Forum

stephendv wrote: »

The heat pump + geyser (hot water tank for US folk), is interesting because it'll let you time shift the usage. I.e. only turn on the heat pump when the sun is shining, which means you can go with a smaller battery bank.

Not sure how that would be any different from putting a timer on your water heater, we had one at home when I was a kid, and they are in use at our pool. Grey box is a brand here in the states. The heat pump water heater will be much cheaper than your original water heater in general.

Newbie to Solar power and very impressed with this Forum

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