My (little) bit for the planet..

Perhaps not appropriate on this forum, but pertinent in this time of world energy crisis!

I have in the last week completed installation of a 20KW Solar system. It has been running for a week. It performs very well, but is is summer now, so that is not a good test yet!

We do have regular cloudy and very misty days here on the coast, and since commissioning on the 12th, we have had 3 days of solid mist with the rest bright and sunny.

At 10.00am during the mist days the system provided 4 to 5KW, while at midday with visibility approx 400meters in the mist, power was 6 to 7KW.

Batteries are 6x5KW/hr Lithium, dischargeable down to 20%. Discharge has been to 58% min at present - using oven, coffee machine, stove etc at night. Geyser is on a timer - 8to10am and 2to4pm, set to 45degC

As I have 3phase lathes, shaper, woodworking machines, etc, the system consists of 20KW of PV panels, with a possible 6KW more to come, a FRONIUS PV to 3Phase inverter ( 15KW) , an MPPT PV to 55VDC charger for batteries and three 10KW 3Phase inverter/chargers.

The latter take DC feed from batteries and when batteries are charged , DC feed from the MPPT battery charger (a 200amp/55V charger). These inverters also reverse roles and can charge batteries when needed.

The PV panels are in three strings - 2 of 600volt strings feed the Fronius 3PH inverter, and one string at 400volts feeds the MPPT charger.

Excess power is fed back into the mains grid.

Unfortunately, our power supplier is behind the times and cares nothing about our carbon footprint...They gladly accept my excess power ( some 10KW/hr for 6 to 8 hours at the moment..) and give me a credit for it - they won't pay me money for it, but credit against my use of their power. Also, they credit at 45% of the sold tariff only, so I have to give them two units to get almost one unit credit...AND any credit I have at the end of a month is lost..does not roll over.

2x600V strings on the ground floor roof.The 1x400V string is on the roof of the 2nd story

Power room - left 3x DC-mains inverters, then (grey box) Fronius PV to 3PH mains, then MPPT DC Charger and right side the main DB

3PH 10KW each DC to Mains inverter/chargers

PV to 3PH mains @ 15KW

MPPT PV Charger, 200amp

6 battery stack 5KW/hr each. Intelligent monitoring system in each pack.

Space above for the next 6 batteries..When I add the 4th PV string upstairs..

10.5KW today at 10H00 this morning

Control panel LCD at various times and loads..Still tuning and playing..

upper left is the national grid - minus numbers are feed into the grid from my PV system. Positive number would be from grid to me.Critical loads are house and workshop - AC loads are underfloor heating, currently off in summer.

I even ran my big 3ph mig welder from the system at 250amps - all it did was halve my power export to the grid!

There are 3ph power monitors on incoming/outgoing grid and on the critical and AC loads and all that data as well as power generated, PV power, battery condition, etc is logged and accessed by network interface. All very neat...

Very impressive, Joe !

MichaelG.

Serious stuff there Joe....looks very impressive.

I would love to tell anyone who comes round to my house "let me show you my POWER ROOM"!!.....brilliant !

Regards

Derek

It does look impressive and expensive. Over what time period will it return your initial outlay?

You may think you are saving the planet but I wonder how big the carbon footprint is for all you gear

H

In the UK we are stymied by eco-hostile constraints on PV installation. For grid tie you have to use special approved panels which thus double or triple the free market price of the same panels. Then you are not normally allowed more than 3.5KW and now may get paid only 5p per KWh that is sold for 49p (a recent tarif I have been given from 1 Jan).
You are not allowed to raise the angle the panels off the roof like you have by more than about 4 inches and if you are thinking of a ground based array to be less obtrusive then you are only allowed a 3mx3m single footprint, ie barely 1 KW.

I think everyone dreams of getting energy independent nowadays but its only a dream for most people

Excess energy in an organised system could be used for mass transport and heating/cooling

All the most successful economies are still heavy coal users

**LINK**

Investing in energy efficiency is still a new financial discipline requiring proper real world expertise

Edited By Ady1 on 19/12/2022 19:11:46

I think it all good and well for those that can afford it, and those in remote places that cannot do anything else, however for the masses this may be a problem, and the concept of decentralised power, which shifts the upkeeping and maintanance to the enduser, is a dream at the moment and not prooved at a scale of 7 Billion plus on the planet. The problems will start coming when end of lifetimes, parts availability versus replacements are vcoming up to the end user AC power must be cheap, because ts the basis of our modern living standards, even digital totally depends on stable good power and everybody connected must have it working to connect, have money(Digital versus cash) available to move, live or go around. This is where we will experience the difference between the choice of an affordable life and if you can afford it a luxury life, or where there is only one choice= a luxury life.........It rather seems some complete new safe centralised power form must come along other than Nuclear and be dirt cheap to support the upward levels depending from it. This is my opinion currently.

Nice install. Ive just completed mine using the Victron kit as well. Its good stuff. My battery capacity is at 10KWh just now but planning to expand it to 25KWh. Its better to be able to store it and use it yourself than get paid a pittance from the energy companies. Sunny Scotland isnt so sunny in the winter but in summer I can generate up to 32KWh per day, no where near what you will manage, but I can also charge the battery at cheaper nightime rates when Im not charging the car. My solar array is 4.4KW but limited to 3.6KW output from the inverter to comply with the energy companies regulations but I think you can install a larger array than that without permission if not feeding back to the grid.

Thank Michael - we will see in time if it impresses me...

Keith (Wyles) - Over what time period will it return your initial outlay?

There is NO chance of return AT ALL! The system is idle now in summer - I am sure it will work hard in winter, and the batteries will be heavily taxed. At my current annual electricity rate, I will break even in 26 years time. And that excludes battery replacement in that period - to replace that pack today is around 15K Pounds.

Harry:

You may think you are saving the planet but I wonder how big the carbon footprint is for all you gear

Not sure I follow. By 'my gear' I presume you mean my machinery? Using the machines,unless one wishes to be pedantic, would not increase my footprint, if I ran from my own generated solar power, surely? The emissions that resulted from the manufacture of said machines is will not grow, nor will the emissions from the manufacture of the Solar system - although replacement batteries means being part of the carbon cycle in the manufacture of the new set...

I don't really understand what you are implying Harry - please explain.

Yes, it would be nice if 'new safe centralised power' came along but I don't see that happening within this century - Even though the entire first world has had the Power Plug pulled from its socket, there is very little real happening to fix the problem - lots of talk and posturing at many summits, while coal mines are re-opened all over the world and the perpetual approach is - lets get through this winter and we will worry about it next year..

And in Africa, power was always and remains a problem for all. Government mentalities in Africa are focused on get rich quick and are fraught with corruption. Namibia obtained 65% of its power from South Africa , on a 6 year contract basis, previously renewed with no issues. The current contract expires end 2023, and SA have said they will only renew for two years, and this time on a non-guaranteed basis - ie, Namibia will be subject to the same load-shedding in place in SA. There is ZERO maintenance taking place on SA's power generation infrastructure with the last new generators installed 27 years ago...SA endures 8 to 10 powerless hours a day, 4 to 5 days a week at the moment, in the major cities...How to destroy a country and its economy....

Its all well to talk of the nuclear powered, wind powered, etc, first world - that may come about when your grandchildren are your age, but it will NEVER happen in Africa or any of the third world.

So even though my 'little' bit is very little, and irrelevant in the scheme of things, when SA pulls the plug on Namibia, and perhaps in the dire times Europe and the UK find themselves in now, and for the foreseeable future, I will still be able to play happily in my workshop!

At least I have a reasonable level of independence, and at the same time am saving a few kilograms of carbon emissions!

Edited By Frances IoM on 19/12/2022 20:07:19

Life for the "haves" in Africa is already like that anyway in many places. Razor wire-topped 15-foot stone walls, security guards and guns are not uncommon. And down in the shanty townships, power is a luxury, not the norm, and supply very spasmodic. It's a whole different world.

Not to go to far off topic...Namibia is today one of the safest countries in Africa - and Swakopmund even more so - there is no tangible 'race' issue in this town at all ( maybe a German/Afrikaner one though...) - Nothing at all like in South Africa, or anywhere else in Africa..We probably have our small population to thank ( less than 2.7million people..) and the fact that the central and northen regions are basically desert. Land grabs gain no-one any thing here - its just more sand...

Anyway, this post was I guess to brag that I am trying to do a little where I can...

Joseph, 20kW set up is awesome. Most of our increasingly popular set ups here in Oz are 6 to 10kW. Take up has been so unexpectedly popular that power companies are closing coal fired powerstations 10 years ahead of previous schedule. Between that and wind turbines, we are rapidly moving towards majority renewable power.

Grid stability has been a fear so the the government/private contractors are setting up some of the world's biggest batteries to suck up the power during the day and dole it out overnight etc. and bring some stability to the grid. Plus big plans afoot for pumped hydro power using solar to pump the water uphill to the reservoir in the day and then then let it run down overnight to generate power. There are other moves afoot to set up massive stored gravitational energy units that use solar power to lift massive weights during the day to a height of 20 stories or so, then let the weights descend overnight to drive generators through some kind of gear train etc.

In other states, when they build new housing estates, every house has a roof full of solar panels, belonging to a power company, not the house, and the house-owners get paid for it, so it all feeds into a co-ordinated grid with batteries for stabilising peak loads etc rather than each house running its own race.

Fascinating to see the technology taking off so quickly and so successfully. With the endemic corruption and almost total "capture" of the Eskom power utility body in SA I reckon having your own supply is a wise move.

And the the naysayers question the carbon footprint of making all the solar panels etc, but the carbon footprint of building a conventional powerstation is huge too, with tens of thousands of tonnes of concrete and steel and plastic insulation etc etc (20,000 gallons of paint!) and continues on every year after construction as coal is mined, loaded onto trains, transported to the power station and then burned, with tonnes of ash to dispose of every day, plus the stack emissions. Then at the end of its life, the power station has to be demolished and countless tonnes of concrete disposed of, steel chopped up and hauled away for recycling, miles of wire stripped of plastic etc etc. IN the long run, solar does work out as a much lower carbon footprint. (And I say this as someone who made a good living at one stage building, running and maintaining coal fired powerstations and industrial boilers and enjoyed every minute of it.)

Excellent setup Joseph, makes mine look a bit feeble at 1.2kW but it works well.

Gren

Joe

My solar system on my roof generates only 4kwh in ideal conditions, I have 12Kwh of battery storage and one sunny day I used the technology built into the batteries inverter to read how much juice was going into the batteries and was amazed when it read 20 amps, on a sunny summers day my system generates a total of 25 kWh so with the batteries, for about 3 months during high summer, we can be self sufficient. Having a tariff that gives us cheaper energy during off peak times, midnight to seven am, during winter, when the sun rarely shines, I charge my batteries at less than half the cost of day rate units to use during the daytime, with the current energy crisis due to the war in Europe I am glad I took the step in installing the solar system, I think it is certainly the way forward for households of the future. At this time when there is a power outage my system isolates itself in order not to feed back into the grid and therefore prevent accidents when the grid is being worked on, I can modify my batteries inverter to make the stored power in the batteries available during a power outage but as we have very few outages at the moment the cost is not justified. Can I say that I am very impressed with your system. Dave W

Pat yourselves on the back, it must be nice to have the money to be able to invest on things like solar panels and electric cars, not everybody has anything left after paying the bills and eating.

Old Mart, how very true.

Awesome!

Are you not allowed to sell surplus energy to neighbours?

You may find some UK figures interesting. Here we generated 4.6% of our power by solar over the last year, but being winter only 1.1% over the past week.

For wind power the figures are roughly 32% and 28% respectively. There is some argument about where, but this is going to be a huge part our power mix in the future.

Coal is a third of solar over the year, but gas still makes up over 40%.

Nuclear is about 17%; most people have accepted it has an important role as a lower carbon way of balancing the base load.

National Grid power sources

Finally, here in Wales we are looking to see if there's a way to harness rain power

Neil

Edit... over the last 24 hours over 48% of UK power was from wind generation.

Edited By Neil Wyatt on 21/12/2022 20:45:01

The fact this gives you energy independence in a part of the world where things are less guaranteed is a big plus, if it helps the environment also that's a bonus, I think it's very impressive personally.