Jump to content
Chris Hobson

Way solar systems are marketed

Recommended Posts

A Facebook page has come to my notice that markets a solar system with a 1.5kW array as a 7.5kWh system and a 4.5kW system as a 22.5 kWh system. I think that is just plain disingenuous. It appears the inverter used is an Axpert. Now I like an Axpert but for the system to run properly there is the issue of floating the batteries. If I had the money I would challenge the cost of one of their systems to demonstrate that they could even average their stated "systerm size" and fully charge their batteries, allowing for 2-3 hours of float charging.

Am I being unreasonable saying they should not be quoting kWh as a system size as their figures are based on theoretical production?

Share this post


Link to post
Share on other sites

New luxury car, from only R13199 (it always ends on 99). The trick is in the "from" keyword, or sometimes "up to", or "your share of", in other words if you put down a 20% deposit, take a 35% residual value, and finance the rest over 72 months... yeah sure... then it will by only 13.2k a month... :-)

In this case, no clear keyword, so definitely a little sneakier than usual. I would be amazed if that 7.5kwh system even gets close to 5. I have 1.5kwp on my roof, I made almost 8.4kwh on one particular day but the truth is that it only really makes above 7kwh two months of the year. Right now I do around 5.8kwh on a sunny day. And that's with a hybrid inverter that can grid-tie :-)

On the other side of the coin, when marketing to the average home user: they generally have no idea what 4.5kwp even means, but a slightly larger fraction of them do know what 20kwh means. It does also use a 5-hour peak solar day in the calculation which technically isn't wrong. So I'm really not quite sure, I suppose if they disclosed those things before sale I would be okay with it.

Share this post


Link to post
Share on other sites

As @plonkster stated , the average person , and I will include myself in that group just before I started my system , don't have a clue as to what a baseload is what his day and night consumption is or even what his peak usage is. They mostly believe that , if you change all your light to LED's then you are saving energy. Even if the LED and the energy savers both use 10 w :) . But they still keep the fluorescent light , that uses 60w , on the whole night  because someone at some stage said that fluorescents use less energy than any other light. O ja and don't forget the good old desktop pc that bugger can rip you a extra 300w just on idle if you are not careful. So whether they say 4 , 5 8 or even 10 would not make much difference BUT I would look at the price they sell the system , if they fall within a reasonable profit margin then I would be okish with it but sometimes these okes charge an easy 150% profit margin and then I start to lift the eyebrows. 

Interesting thing I red over the weekend , SA is currently using less energy than in 2007 when all this load shedding started! I for one maintain that the Zuptas had a scheme to put SA under pressure to push MUCH more money towards Eskom unfortunately the residents of SA is much more resilient and adapted or should I say luckily....

Share this post


Link to post
Share on other sites
29 minutes ago, PaulF007 said:

had a scheme to put SA under pressure to push MUCH more money towards Eskom unfortunately the residents of SA is much more resilient and adapted or should I say luckily

They had a plan alright, but they pulled it at the worst possible time. They couldn't have known, bless their souls, but all this nonsense started around 2007/2008(ish) as JZ became president of the ANC and all those corruption charges and shower-gate strangely got swept under the carpet. Incidentally, 2008 was also the year the Americans pulled operation sub-prime, and then came the big one... in 2012 PV panels dropped by half, even in 2015 it shed another 10%, and just this year we've seen it drop to below ZAR5/Wp despite our poor exchange rate. I speak under correction, but costs now must be less than 20% of what it was in 2008.

These guys single-handedly started the small-scale renewable energy sector in this country, and the guys who are worst hit remains the poor.

Share this post


Link to post
Share on other sites
On 7/24/2017 at 9:00 AM, PaulF007 said:

As @plonkster stated , the average person , and I will include myself in that group just before I started my system , don't have a clue as to what a baseload is what his day and night consumption is or even what his peak usage is. They mostly believe that , if you change all your light to LED's then you are saving energy. Even if the LED and the energy savers both use 10 w :) . But they still keep the fluorescent light , that uses 60w , on the whole night  because someone at some stage said that fluorescents use less energy than any other light. O ja and don't forget the good old desktop pc that bugger can rip you a extra 300w just on idle if you are not careful. So whether they say 4 , 5 8 or even 10 would not make much difference BUT I would look at the price they sell the system , if they fall within a reasonable profit margin then I would be okish with it but sometimes these okes charge an easy 150% profit margin and then I start to lift the eyebrows. 

Interesting thing I red over the weekend , SA is currently using less energy than in 2007 when all this load shedding started! I for one maintain that the Zuptas had a scheme to put SA under pressure to push MUCH more money towards Eskom unfortunately the residents of SA is much more resilient and adapted or should I say luckily....

Here's something interesting. I brought home some rackmount servers to setup a cloud cluster. 4 servers and a switch and just as I switched them on this evening, I thought I'd check what the damage will be on my batteries / electricity bill. The 4 server cluster doesn't draw much power, about 300W in total. It's not doing much, yet. 

 

@Chris Hobson perhaps part of the marketing technique relies on the fact that most people read their electricity bill in kWh?

Share this post


Link to post
Share on other sites
On 28/07/2017 at 10:27 PM, SilverNodashi said:

 

@Chris Hobson perhaps part of the marketing technique relies on the fact that most people read their electricity bill in kWh?

I am perhaps just a grumpy old git but if one wants to quote kWh then at least have the quoted production not from the realm of fantasy. Plonky and I have exchange several FB pages where the production is just too good to be true.

Share this post


Link to post
Share on other sites
On 2017/07/23 at 9:33 AM, Chris Hobson said:

A Facebook page has come to my notice that markets a solar system with a 1.5kW array as a 7.5kWh system and a 4.5kW system as a 22.5 kWh system. I think that is just plain disingenuous. It appears the inverter used is an Axpert. Now I like an Axpert but for the system to run properly there is the issue of floating the batteries. If I had the money I would challenge the cost of one of their systems to demonstrate that they could even average their stated "systerm size" and fully charge their batteries, allowing for 2-3 hours of float charging.

Am I being unreasonable saying they should not be quoting kWh as a system size as their figures are based on theoretical production?

Here is another dubious declaration made by a Solar installer and supplier. This was sent to me by a client. This was part of a FB post.

And quote.

"PV Green Card status offers the consumer peace of mind that their installation complies with current SANS regulations. 

Not using a registered, licenced contractor to do your installation can void your insurance and may also prevent you from getting occupancy from the municipality."

As far as I am aware, any installation that has been issued a COC is legal and insurable?

 

Unless I am misinformed, these guys are misleading people to get business!

Share this post


Link to post
Share on other sites
1 hour ago, plonkster said:

What is that? ^^^

In a newly constructed home you would be provided an "occupation certificate" on completion by a building inspector, after providing the inspector with the necessary certificates (including Electrical COC).

Share this post


Link to post
Share on other sites

It doesn't matter what industry you want to compare they all bend and fudge the figures to sound more favourable to the customer. Look at VW and their diesel emission figures, look at a variety of batteries they almost never perform as stated (unless you have studied the fine print and their odd test conditions) and our trusted government they would never lie to us or investors......

Share this post


Link to post
Share on other sites
1 hour ago, seant said:

Look at VW and their diesel emission figures

The odd thing about that scandal is that the figures didn't even benefit them. Let me explain. Their system would detect when it was being tested and use alternate values during the test. This means that during the test, it would have lower emissions but higher fuel consumption than it does on the road. The fuel consumption figures that are used in marketing and on the big sticker on the windscreen is from the official test however. In other words, they built a car that was "better" on the road than advertised. Which is extremely odd really... one would think that once the vehicle is off the showroom floor the customer has made peace with the advertised fuel consumption and would be unlikely to complain or be otherwise unhappy.

Share this post


Link to post
Share on other sites

But it did affect VW sales cause without passing the emissions tests that range of 'fuel efficient cum low emission ' vehicle wouldn't have been sold in the states. Never mind the emissions which were altered in the test state. I watched a short documentary now the whole thing and they showed a very diffrent emissions profile , far worse than would be allowed.  They also said that it was almost common place for manufacturers to crook the emission tests one way or another, it's just VW was made to look like the only guilty party.

Share this post


Link to post
Share on other sites
2 hours ago, seant said:

But it did affect VW sales cause without passing the emissions tests that range of 'fuel efficient cum low emission ' vehicle wouldn't have been sold in the states

True. But they could have done the same thing without having to crook it. They could have just put in the new map, took the fuel-efficiency knock on the chin, and that would have been that. Instead they made a complex detection system to switch between the two, essentially for no additional gain.

What I am saying is this one bucks the trend a bit. It's not really an example of people cheating to make money. They could have made the same money without cheating.

If it was about making money in the states, the right answer would have been not to cheat (because there was little or no benefit). Instead... this smacks of someone not wanting to kill the hard work he did for several months just because someone in a different country has different ideas... (not saying that is what happened... it just feels like it).

My argument banks on one thing though: That I assume the money is made on the sales floor. The car is essentially sold based on the sticker value as determined in the non-cheating test, so the cheat had no benefit on the sales floor. Of course I may be mistaken in this belief: Maybe they thought it would help them sell more cars.

Share this post


Link to post
Share on other sites
19 minutes ago, The Terrible Triplett said:

If you have less emissions, using more fuel, is that better than using less fuel with more emissions?

It is better to burn more fuel. It's once again an incredibly interesting field, with an awesome word that not many spell checker even knows: stoichiometric. You want the air/fuel mixture to be stoichiometrically correct. When it is, it burns cleanly. On either side there is trouble.

If the mixture is rich, then you spit out unburnt hydrocarbons (which is bad, don't really want those carcinogens in the air), but it also means you're ejecting fuel from your exhaust without burning it, which is obviously bad. In addition you also make more carbon monoxide, because you run out of oxygen in the combustion process and the last dregs of the process has no choice but to bind with single oxygen atoms instead of pairs. Carbon dioxide is much friendlier than carbon monoxide. Carbon dioxide can be used by plants.

On the other hand, if the mixture is lean, you make more Nitrous oxides, or Nox. Nox is bad because it makes acid rain. In addition, a petrol engine that runs lean runs hotter.

Now... in the 80s and before that, and especially with carburetors, there was a practice where petrol engines were made to run lean in low-load conditions. It saved fuel when you were cruising, and the little bit of hot running was no problem in such low-load conditions. What has happened now, with the new emissions laws, is that you are no longer allowed to do this.

It gets more complex. The catalytic converter in modern cars has the capability to turn bad gasses into less bad gasses, for example, it can turn carbon monoxide into carbon dioxide. For this to work, it needs the right amount of oxygen in the exhaust gas, and the right temperature too. And this is also dependent on how you work the fuel/air mixture.

So short answer: Yes... we do indeed have to burn more fuel to get cleaner air, and cleaner air is probably more important.

Enter Diesel engines: They always run lean. They suck in clean air, compress it, and then squirt some Diesel into it. The diesel droplets always burn from the outside surface in, and there is always enough air, but it still makes carbon monoxide because a large droplet of Diesel burning exhaust the immediate oxygen supply in the area of that droplet (hence all the tech moving to higher injection pressures to squirt a finer mist), and because it runs lean it makes Nox. Which you then again deal with by treating it with some kind of exhaust device, Toyota calls it the D-CAT, and again the same things happen: Got to put in more Diesel to make it run at the right temperature.

What VW did was to run it lean and save fuel at the expense of more Nox.

At the moment Diesel is actually falling out of favour in Europe because it is easier to do this stuff with petrol exhaust gasses. And Diesel has that horrible black soot.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×