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Fronius’ New Hybrid Inverters Only Use BYD HVM/HVS Lithium Iron Phosphate Battery

Sunday, May 30th, 2021

Current Generation are distributors and integrators of the BYD are pleased to supply of batteries for Fronius inverter products,

Fronius, a premium inverter manufacturer which is well respected in the world, have chosen BYD as their battery partner, making BYD the only approved battery for use with the new Gen24 line of Fronius inverters. This move reaffirms the standing of the BYD products.


The high voltage BYD Battery-Box Premium Line has two models, the smaller HVS, and the larger HVM. The HV Premium Line from BYD is compatible with GEN24 Plus inverters, both the single phase Primo range and three phase Symo range.

The storage capacities available are 5.1–10.2 kWh for HVS and 8.3-22.1 kWh for HVM.

The voltages of the HVS and HVM differ. The more powerful HVS modules have a nominal voltage of 102.4 V each. By contrast, the HVM modules have a nominal voltage of 51.2 V per module. These different voltages subsequently lead to different charging and discharging characteristics.

Fronius has achieved a true grid back-up solution, with the BYD Battery-Box Premium HVS/HVM, allowing even three-phase loads to be used in a grid failure situation.

Like its predecessors, the Battery-Box Premium HVS/HVM is based on lithium iron phosphate – one of the most reliable storage technologies. The battery has a modular structure and can be expanded in steps of 2.6 kWh (HVS) or 2.8 kWh (HVM). This means that there is nothing to prevent the storage being expanded at a later date.

Another advantage of the BYD HVS/HVM is there is the option for the parallel operation of up to three battery storage systems. This enables higher storage capacities for larger household needs or small commercial systems.

The floor mounting allows the installation and commissioning process to be carried out quickly and easily.

By combining the BYD Battery-Box Premium HVS/HVM with other sectors such as heat supply or e-mobility, it is possible to achieve very high self-consumption rates and self-sufficiency levels. This results in maximum independence in the home.

Talk to Current Generation about your options, Trade enquiries welcome.

Posted in Miscellaneous

kW and kWh: What Does it Mean?

Friday, April 20th, 2018

This article was originally published on Solar Quotes, the original post can be found here.

So, what is a kW & a kWh?

And what is the difference between a kW and kWh?

An older style meter showing kWh

Let’s start with what each letter stands for:

  • k stands for kilo – which means “one thousand”.
  • W stands for Watt – which is a measure of power.
  • h stands for hour – which is a measure of time.

So kW means kilowatt which is 1000 Watts, a measure of power.

Notice that, if you like to keep pedantic electrical engineers like me happy, the correct way to write it is always with a small k and a capital W.

The size of a solar system is defined by its peak power, often denoted as kWp (the p standing for ‘peak’), e.g. a 1 kWp system can produce 1 kW of power per hour when operating in line with the testing parameters.

kWh stands for kilowatt-hour; a kWh is a measure of energy (not power).

If your solar panels (for example) continuously output 1kW of power for a whole 60 minutes, you will have produced 1 kWh of energy.

The amount of electricity you use (or generate) is defined in kWhs. e.g. “My solar system produced 4 kWh of electricity today!”

So at the highest level: kW measures power, and kWh measures energy.

Why is the difference between Energy and Power important?

  • Power is the rate at which work is performed or energy is converted
  • Energy is the ability to do work on objects

It is very common for people to mistakenly interchange the terms energy and power as if there is no difference. Most people do it all the time without noticing. It drives electrical geeks up the wall.

For example, if someone is talking about their electricity usage and says, “I used 8kW yesterday”, they probably mean that they used 8 units of electrical energy yesterday. In this case they should really say, “I used 8kWh yesterday”

Yeah, yeah I know what you are thinking: Who cares?

Well it is actually quite important if you are buying a solar system. If someone says they need a solar power system to produce 8kW, they might end up being quoted an 8kWp solar system. Which will cost about $24,990 + installation at today’s prices and produce about 32kWh per day.

If, what they actually meant was that they need one to cover an energy usage of 8kWh per day, then they really need a 2kW solar system which costs about $8,375.00 + installation at the time of writing!

So please don’t confuse kW and kWh. If you do you may end up with a solar system that is completely the wrong size!

Top tip for filtering out the worst solar salesmen: Ask them to explain the difference between a kW and kWh. If they get this wrong how on earth are they gonna understand your requirements? A lot of cold calling door knockers will fail this test in my experience.

The technical bit for those that are interested:

  • Energy – measured in Joules (J); energy is the capacity of something to do work.
  • Power – the rate at which energy is used; power is measured in Watts (W).
  • 1 Watt – the rate of energy usage, being 1 Joule every second (J/s).

Posted in Miscellaneous

Tilt Frame or Flush Mount Your Solar Panels?

Friday, April 20th, 2018
Should you put your panels on tilt frames?

Tilt frames are used to get solar panels to the optimum angle and maximise power output.
Here is really common dilemma:
“I’ve got 3 quotes for solar: The first company says my roof is at the wrong pitch and wants to charge me hundreds of dollars extra to put my solar panels on tilt frames to optimize the amount of electricity I get. The second mob say it is fine to just put the panels flush on my roof and the third guy says that, yes my roof isn’t at the perfect pitch, but the best solution is to mount them flush to the roof and simply add an extra solar panel to make up for any reduced power output.

Now I’m really confused! Help!”

The problem here is that there are two extremes of solar installers:

At one end of the spectrum you have “The Solar Purist”.
They are only happy if the solar panel is positioned for the absolute optimum power output – they are a perfectionist, highly technical, and have been in the industry since the dawn of solar, when solar panels cost 10 times what they do today.  They think a few hundred dollars is a small price to pay to squeeze a bit more power out of those precious solar panels.  And please, never, ever suggest to them that they use a non-German inverter.
Then at the other end of the scale – you’ve got the “She’ll Be Right” Solar Installer.

They just want to get the install done. If you’ve got a roof, and it doesn’t face south and it’s not completely shaded they’ll bang the panels on, and move on to the next job.We believe that the best installation for your home is somewhere in the middle

The best solution to maximize return on your investment.

You need to consider the financial consequences for each option and then decide whether tilt frames are a good investment or not.
So let’s look at a typical scenario where tilt frames would be an option and see which of our 3 original options makes the most sense from an economic perspective:

To Tilt or Not to Tilt – that is the question

How to work out if tilt frames make sense or not:
Imagine you have a house in Nelson with a North facing roof that has a very shallow slope of 10° and you want to install a 3kW system.The perfect tilt angle for solar panels is the same as the latitude of the install location. Nelson has a latitude of 41°.So therefore the panels should be of the Latitude.
So if we follow those guidelines, we’d have to use tilt frames for all our solar panels right?
Panels at the perfect Angle:
If we crunch the numbers , then we can quickly work out that 3kW of north facing solar panels at the perfect angle of 41° will produce 12.0kWh per day averaged over 1 year.
If we value our electricity at 25c per kWh, then that earns us $1095 per year.Panels at 10°
If we crunch the numbers for 3kW of North facing solar panels at only 10° then we discover that we get 11.6kWh per day which makes us $1058.How much do tilt frames cost?
Assuming our 3kW system uses 195W panels, the extra cost of tilting 16 x 195W panels should be around $450.So to make an extra $47 per year, we are going to be spending $450.About a 9 year payback.Whether you think this is a good investment is completely up to you. But your solar installer should give you the numbers so you can make an informed decision!

I personally wouldn’t bother, mainly because, if you use tilt frames on your roof, you can fit fewer panels on that valuable roof space.

Because you need to leave extra space between the panels so that one row of panels doesn’t cast a shadow on the row behind it. I also think that tilt frames are not so aesthetic to look at . But perhaps that is just me.

What about adding an extra panel?
The third option you have – is to make up for any lost power by simply adding an extra solar panel.
A few years ago, when panels were 5 x the price, this would have been an insane suggestion (and some old school solar installers still think it is a terrible waste!) but in 2012 it can make a lot of sense.

The cost of one extra 195W panel will be about $440. Installed flush to your roof, this 17 panel system will generate 13.0kWh per day and make us $1186 per year.

So your extra $440 investment is returning you an extra $169 per year compared to the 16 panel system mounted on tilt-frames at 41°.
I’d say that the extra panel is a much better investment that the racking.

The third installer was right!  (Oh! That’s us!) Call Current Generation today for common sense facts.

Note: One thing that you don’t want is completely flat panels (angle = 0°). You want them to slope at least 10° so that the rain flows down the slope and helps the panels self clean.

Posted in Miscellaneous