Germany paid for the world to have cheap Photovoltaic Electricity!

In reply to the following question:

Because in the 1980's Germany realised that coal, oil, gas and nuclear energy would be unaffordable by 2020 and they decided to do something about it.

In 1991, they implemented Feed In Tariffs (FITs). At the time the FITs would have been R12 if they had been in the City of Cape Town, whereas Cape Town electricity was 10 cents per kWh in those days.

Germany saw the big picture and created the word's biggest supplier and experts of Renewable Energy equipment. Germany essentially paid for the rest of the world to have cheap electricity!

Germany decided to get to 20 by 2020, ie 20% Renewable Energy by 2020. They got there in 2013 and change 20 to 30 by 2020. Last year they got to Grid Parity with Grid Tie PV and started incentivising Battery Based Systems.

See attached graph which shows the graphs over the past few years:

Is R100,000 a lot of money?

A friend installed a solar PV system for R100,000, which uses partly solar photovoltaic electricity from the sun, partly batteries, and partly Eskom.

Was the R100,000 investment worth it?

In summary, the cost is R21,820 per annum instead of R29.591 per annum, but there are some assumptions, so read on. And that's just in the first year. In the second year the cost is R22,569 instead of R33,327.

Here are some calculations:

Besides the security of supply advantages and no load shedding advantages and reducing one's carbon footprint advantages and the advantages of all one's friends wanting to visit and see what one has done and the advantages of being able to continue working from home, assuming one does that, there is also a saving in what Friend has done, especially once rates go up in July 2015.

Some calculations:

R100,000 is R1,338 per month at 10% over 10 years. Or R16,056 per annum. Using the Standard Bank calculator at https://www.homeloans.standardbank.co.za/servlet/com.sbsa.sbhl.bondcalc.business.MainCalcServletInternet?page=Main_MonthlyRepayEntry

Note that the R2.10 per kWh tariff that I have used in the following calculations is the City of Cape Town Electricity tariff assuming a 13% increase in July 2015.

If Friend used 32 kWh per day and now uses 6 kWh per day in summer and he used 45 kWh per day in winter and now will use 9 kWh, then assuming summer is 6 months and winter is 6 months, then :-

32 kWh * 183 days + 45 kWh * 183 days = 5,856 kWh + 8,235 kWh = 14,091 kWh * R2.10 per kWh = R29,591 per annum.

6 kWh x 183 + 9 * 183 = 1098 + 1647 = 2,745 kWh * R2.10 per kWh = R5,764 per annum.

So he was paying R28,182 per annum and is now paying R16,056 + R5,764 = R21,820, which is less than R29.591.

He also switched to gas for part of his cooking, but he still has R7,771 to play with before he breaks even. And that is only in the first year. In the second year when prices increase by 13% again, his savings will be even greater as his cost will be R22,569 instead of R33,327.

Change your thinking: Does Solar Electric Renewable Energy really cost more?

People complain about the high cost of Renewable Energy. Here is my answer to two of them.

Hi Willem and Mike. You both need to think about it a different way:

1. What will your cash flow be with a solar system? If you are paying R2,000 per month now, and you can install a system, without batteries, and it costs you R1,800 per month, then even though this represents R180,000 of capital, you should do it. A grid tie system without batteries can be paid over 20 years at 10% interest rates.
2. Lots of people, especially those who work from home, or SMME's, and even the big boys, are installing backup systems, which don't supply their entire needs, but which for about R100,000, give them security of supply during Load Shedding and BTW, also reduce their normal electricity cost.
3. In 2008, I decided to spend R200,000 on a backup system for my house instead of buying a new Renault Clio. I therefore initially spent R5,000 per month instead of R600 per month. Over 5 years this R600 would have become R1,800 with increases. Eventually my "car" was paid off (in five years), in December 2013, and in January 2014, my electricity bill dropped to R400 per month, instead of R1,800 per month that it would have been now.
4. If the government allowed "rich" people (by rich people I mean taxpayers) to install their own systems before Tax and before VAT, just like IPP's can, then these peoples's battery based systems would already save them money.
5. If the government had spent the R300 billion it has spent on Medupi and Kusile, so far, on poor peoples' houses, then it could have made 6 million of these houses into power stations already.

So it's just a matter of changing our thinking. And that is the problem.

What if it rains and I've got a solar electric photovoltaic (PV) system?

What if it rains and I've got a photovoltaic (PV) (solar electric) system?

A question I get all the time!!!

Well it's raining now (13th February at 11.15am) and my 1 KW PV system is generating 190 Watts.

We are currently using less than 190 Watts in the house, therefore we have excess energy being used to recharge the batteries. If we have a power failure now or Load Shedding, we won't use our batteries.

One should also note that Germany is the world's biggest PV installer and they've been installing in a big way since 1991. They only have 40% of the solar irradiation of South Africa and therefore for the same capital cost, South African PV users get 2.5 times the output as compared with German PV users.

Battery related questions in a backup system which can be used during Load Shedding in South Africa

Here is an answer I just posted on Facebook: "Have I been given the wrong info? I hear that the battery replacement cycle is rather short and therefore costly."

Hi Pat.

If you buy the 100 or 105AH "Solar Storage" batteries that look like car batteries, but which are called "Solar Storage", they will last about 2 years and then even though they say that are "sealed" I had 8 of these batteries and managed to refill them after two years to that they lasted 4 years. But their performance wasn't great.

18 months ago I upgraded to "Deep Cycle" batteries, 260 AH 12 Volt SonX batteries. The 4 SonX cost about R20,000 instead of the first set which cost about R12,000. But they are firstly 520 AH at 24 Volts instead of 420 AH at 24 Volts and secondly their performance is excellent. They last a lot longer than the original batteries.

And then the specification says they should last 7 years, but I'm hoping they will last longer than this, but even 7 years will be excellent. Note that in a battery system design, one should design the system to not use more than 30% of the battery capacity on a regular (daily) basis and only use 50% on a very irregular basis. This way the batteries are looked after and will last the specified time.

Having said all this, the inverters should last 12 years and the most of the photovoltaic (PV) panels are guaranteed for 30 years, with the PV panels performance deteriorating to 90% of their rated capacity after 12 years and to 80% of their rated capacity after 30 years.

So relative to inverters and PV panels, batteries don't last as long and therefore need to be replaced more often and therefore are relatively more expensive. But the benefits they give you far exceed their costs, in my opinion.

One should also note that if you have a "battery system", you need more components than on a "grid tie system" without batteries and therefore a system with a battery costs more than just adding the additional battery bank. And there is more maintenance on a battery system although the systems can be programmed to look after themselves and send warning system messages or emails or sms's if there is a problem.

Set 1: Price R12,500: Lasted 2 years. The second 2 years battery performance was really poor. Equals R6,250 per annum.

Set 2: R20,000: Should last 7 years: R2857 per annum.

These calculations exclude interest and the Cost of Capital, but I think the point is made.

Rain and Solar-Electric PV Photovoltaic Systems

What if it rains and I've got a photovoltaic (PV) (solar electric) system?

A question I get all the time!!!

Well it's raining now and my 1 KW PV system is generating 190 Watts. It's a thin film system so it will be interesting to see how crystalline systems are performing.

We are currently using less than 190 Watts in the house, therefore we have excess energy being used to recharge the batteries. If we have a power failure now or Load Shedding, we won't use our batteries.

Gecko Rock Solar Electric PV Installation in September 2010

Gecko Rock 8 minute installation and learning video

(as at 19th February 2014, over 2,000 people have watched this video)

(I removed the video in June 2016, and put it back in December 2016)

Gecko Rock (Jonathan Deal) Interview 1 year later

(I removed the video in June 2016, and put it back in December 2016)

Videos filmed and edited by Antony Stone at Big Bang Stunts and Effects

The Team:

Designers: David Lipschitz and Peter Burden
Main Installer: Peter Burden
Metalwork: Designed and installed by Steven Mulder
Videos: Antony Stone

The Client:

Jonathan Deal at Gecko Rock

Specifications:

Overview

• 1.6 kilowatt photovoltaic array with 24 Volt 675 Amp Hour battery bank and 1,200 watt inverter charger with generator backup
• 8 kwh of battery backup
• 8 kwh of average daily solar production from the photovoltaic array

• Location: Gecko Rock, 25 km South South East of Touwsriver, Western Cape, South Africa
• Solar Resource: approximately 5 average peak sun-hours
• Photovoltaic Array Size: 1.62 kW (1,620 watts)
• Nominal Voltage Batteries: 24 Volts
• Nominal Voltage Array: 72 Volts
• Array Voltage at Max Power: 108.6 Volts
• Array DC Current at Max Power: 15 Amps
• Battery Amp Hours: 675 Ah (amp hours) at 20-hour discharge rate. Multiplied by 24 Volts and allowing for a 50% maximum depth of discharge = 8.1 kWh in the batteries for overnight and overcast periods
• Record Low Temperature: unknown; we have allowed for Minus 15 degrees Celsius (during day light (operating) hours)
• Average Low Temperature: 2.2 degrees Celsius in July
• Average High Temperature: 28.6 degrees Celsius in February
• Average Daily Production: 8.1 kWh
• Average Electricity Available after taking account of efficiencies (or inefficiencies): Allow 7% for inverter loss; 20% loss for battery charge/discharge from photovoltaic array; and 2% voltage drop on the cabling: 8.1 kwh * 0.93 & 0.8 * 0.98 = 5.9 kwh per day of usable electricity (daily average over the entire year)

PV System Components:

• 9 Tenesol TE1700 at 24 Volt nominal: 180 Wp STC, 36.2 Vmp, 5 Imp, 44.4 Voc, 5.4 Isc (133.2 Volts open circuit for the array (at zero amps, i.e. first thing in the morning) and 16.2 Amps Short Circuit current for the array)
• Array: 1 “string” of 3 “panels” with 3 “modules” in each panel. Total 9 Modules, 1,620 Watts total
• Array installation: Dual-axis (manual) trackers designed by SolarSells, and enhanced, built and installed by Intricate Steel
• Inverters: 1 x 24 Volt Victron 1200 Watt multi-plus Inverter/Charger allowing 24 Volt DC to 220 Volt AC conversion of electricity and allowing automatic synchronisation of a generator input into the system to supplement the batteries in the case of long cloudy periods
• Solar Charge Controllers: 1 x 80 Amp Outback FM80 MPPT (maximum power point tracking) controller. The FM80 allows array sizes up to 2,000 Watts when charging at 24 Volts. The FM80 allows one to use a higher output voltage PV array with a lower voltage battery, such as charging a 24 VDC battery with a 72 VDC array. This reduces wire size (and cost) and power loss from the PV array to the battery/inverter location and maximises the performance of the PV system
• Batteries: Deep Cycle: 12 x 6 Volt Trojan T105′s in 24 Volt nominal configuration, i.e. 3 banks (in parallel) of 4 batteries (in series) making 24 Volts nominal and 675 Amp Hours capacity. Each 6 volt battery weighs 28 kg making a total battery bank weight of 336 kg. We expect the batteries to last about 8 years with an average discharge of 20% and a maximum discharge of 50%. The batteries have a 2 year free replacement guarantee assuming they are looked after and “watered”, i.e. the battery de-ionised water is checked and filled as required. We can tell how the batteries have been used by looking at the information on the Victron Battery Status Monitor. The Trojan batteries are designed in the USA and assembled in Cape Town
• Generator: 5 kw Honda
• System performance metering: Victron Battery Status Monitor BM 600 for DC performance and battery monitoring; Efergy e2 Electricity Monitor for AC performance and historical AC kwh tracking
• 2 Earth spikes and open earthing cabling allowing all metal work to be earthed. System and Equipment negative grounding. We have used USA NEC Article 690 rules as far as possible as there aren’t standards for PV systems in South Africa yet.

Update:

Subsequent to this original installation, Jonathan upgraded to 3 x 1.6 KW Victron Inverters giving 4.8 KW. He also upgraded his battery bank to 1125 AH at 24 Volts. Interestingly he discovered that he doesn't need to cook with gas anymore and that he can power his cooking with his microwave / convection oven. This provided an unexpected saving with the system.

When do we get to grid parity

This graph for home owners in the City of Cape Town, using updated information from the IRP, eg 8% increases till 2015, then 16% increases (pages 20,21). We got to grid parity in July 2012. This is the point that a home owner can produce electricity with PV (photovoltaic) panels, using net metering, at the same price or cheaper than they can buy it. Net Metering means buying and selling electricity at the same price.