How to Choose to right Size Off-Grid Power Inverter ?? August 04 2020

Q: Firstly, what is an inverter?

A:  A device which changes direct current (DC) into alternating current (AC) Power.
Example: It may turn (convert) 12v, or 24v or 48v DC into 230V AC power (so you can run standard AC appliances that you would normally plug into the wall).

Q: What size of inverter should I use?
A: The size you choose will depend on the watts of the appliance or tool you want to run (find the power consumption by referring to the specification plate on the appliance or tool). We recommend you to buy a larger model than you think you’ll need (at least 10% to 30% more than your largest load).
Example: You want to power a computer with 20” LED screen and a lamp. Computer and Screen: 300 Watts. Light Wattage: 75 Watts.
Total Needed: 375 Watts.  For this application, you would need a minimum of a 450 Watt inverter but we would recommend a 600w inverter which is the MINIMUM wattage we would supply.

You should always consider a larger unit than your minimum requirements, as there will likely be a time when you wish you would have bought a higher capacity model. If the wattage of the appliance or tool is not listed explicitly on the specification, you may use the following formula. Multiply: AMPS x VOLTAGE = Watts.

Example: On the microwave shows 5.22 AMPS for continuous use. The
Wattage is 5.22 AMPS x 230 V = 1200.6 Watt.

Q: Why can the 1500 Watt inverter not run my 1200 Watt microwave?
A: The power commonly advertised for microwave ovens are the cooking power (the power delivered to the food) not the power actually consumed by microwave oven. The microwave ovens might consume 40% to 100% more than its advertised cooking power. The recommended inverter to run 1200 Watt microwave is 2500 Watt or larger.  Often the Microwave manufacturers only show the "constant" wattage rather than the peak wattage that their unit will use.  Many microwaves cycle the power (on and off quickly) to give a lower constant wattage shown but in reality they are still using the higher peak wattage (from the inverter) even if it's only for a short time. 

The best microwaves for Off-Grid usage are the Panasonic INVERTER Microwaves as you have the ability on these units to run them at half power and rather than cycle the power (with high peaks) the power input / output of these units is able to keep constant at a lower rate, or which ever power level you set it to.  A 1200w Panasonic Inverter Microwave will typically run happily from our 2.2kW Inverters while many other cheaper 1200w microwaves may not.

Q: What is meant by the terms “continuous wattage” and “peak surge wattage” on the inverters?
A: The “continuous wattage” is the wattage that the inverter can supply 24/7 as long as the DC input power supply is in good condition (usually, the DC power supply is a car battery) The “Peak surge wattage” is the maximum wattage that the inverter can supply for very short period of time (a split of a second or sometimes 1 second or a half second etc)

Note: Induction motors such as air conditioners, refrigerators, freezers, microwave ovens, and pumps may have a start up surge of 3 to 7 times the continuous rating. Heat generating appliances such as hair dryers and water heaters will have high peak surges as well.

Example: If the microwave oven has peak surge which is 4 times the continuous wattage, the 1200 Watt continuous microwave ovens will have 4 x 1200 Watts = 4800 Watts peak surge. The recommended inverter to run 1200 Watt continuous and 4800 Watt peak surge microwave is 2200w constant / 4800 Watt Peak Inverter or larger. In general, induction motors require an initial surge of power to start up (“starting load” or “peak load”). Once started, the tool or appliance requires less power to continue to operate (“continuous load”).

Q: What is meant by inverter efficiency?
A: Inverter efficiency tells you how much power (as a percentage) is lost in the conversion.
Example an inverter with a 90% efficiency rating will have a 10% loss.  This means to run a 1000w load / appliance you are actually using 1100w of real DC power / battery power etc.

Q: What is inverter overhead power consumption?
A: When an inverter is producing ANY AC output (even just to run a 10w LED light bulb for example) it will have an overhead power consumption (per hour).  Typically for many larger inverters eg 3kW - 5kW in size this may be around 50-70w (per hour) and in some inverters cases this could be as high as 120-140w (per hour).  With smaller inverters (eg 2000-2200w size) you are often looking around 30w per hour overhead power consumption, so that usually needs to be added into your 24 hour power consumption calculation to get a more accurate power consumption

Q: What is idle power consumption?
A: An inverter when it has NO load (0w of load) running can sometimes enter into an IDLE power saver mode, and sometimes that may bring the overhead consumption of the inverter down from 30w to say 15w for example (saving you some power per hour).  The only problem with this is that in order to kick the inverter OUT of power saving mode back to delivering a nice constant stream of power often requires running at least 120w worth of loads (eg switching on a kettle or a TV screen / computer screen etc), however if you were just switching on 1-2 x 10w LED light bulbs then often with just a 10-40w load the inverter would NOT have enough load present to KICK it out of Power Saving Mode and as such you get flickering of lights or other weird problems and issues.  As such we usually recommend for MOST clients to NOT enable the Inverter Idle Power Saver Feature as usually for most people it will cause many issues and only result in headaches rather than any real world power saving.  For all of our power calculations we always factor in for an inverter running 24/7 in normal output mode with it's normal overhead power consumption and we recommend you calculate in this manner also.

For this reason the default setting for most (actually almost all) inverters is with the power saving mode turned OFF as the default setting.  Some AC appliances will refuse to run correctly when it's turned on hence we in 99% of cases we don't recommend enabling it.

Q: What is Pure Sign Wave and what is Modified Sign Wave / Square Wave Inverter?
A: Inverters can be built to 2-3 different main AC output power standards and these are typically split into Pure Sign Wave Output (a nice rolling AC Sign wave) which is compatible with 99.99% of normal AC appliances, and the other type is the cheaper Modified Sign Wave (otherwise known as a Square Wave) AC Output.  We ONLY recommend and supply the Pure Sign Wave Inverters as these run happily with normal AC appliances without causing issues.  In turn inverters that have a modified sign wave / square wave can sometimes shorten the life of some AC appliances or cause issues / problems because of the more squared edges and less smooth power (for the AC Output curve) of the AC power that they supply.

This is now the end of this posting regarding Small / Mobile Off-Grid Power inverters, we hope that you were able to learn alot of useful information. If you need info regarding larger off-grid Inverters eg to run 5kW or 10kW or 15kW worth of loads, or regarding on-grid or hybrid inverters, or if there's a question you have or something that you are confused about or something we've not covered that you want to know about please feel free to email us or fill out the contact us page, or give us a call so we can best assist you further.

Why is there such a mixed experience with solar power / batteries? April 18 2020

How can 1 person have such a great experience and another person have a bad experience with batteries, solar panels and solar power systems ?

Solar and Battery Confusion ??

It's recently come to my attention that there are many grey market parallel importers out there who simply just import and sell items for no other reasons other than to simply make profits.  Sadly it's the intention of these people usually to just be interested in making the profits (as their primary motivation) but not being able to give correct real world advanced technical advice or technical support to their clients.

This then has lead to many people wondering WHY items they purchase elsewhere gave them a poor experience and why items they purchased from us gave them a great experience?  In their minds they thought they were buying what looked to be the same (or very similar) items.

We've heard this with batteries, inverters, solar panels and entire solar systems in fact.  In some cases we've seen some people only get 2 years of life from their batteries that they expected to get 10 years life from, and in other cases their entire system yearly power production was down to 40% of what it should have been (they had lost 60% of their output) and other similar occurrences.

With many items we supply at Hitek we've done thousands of hours of R&D (research and development and technical testing over many of our key items combined) to ensure our products and systems actually deliver great results for real world NZ conditions.  Often many of our items we get produced for us will have changes or internal variations or adjustments made specifically at our request so that they deliver a better real world experience for our customers here in real NZ system conditions, yet when people try to source their own version of an item it will often be a different spec internally from what we are supplying and in turn it won't perform as well in real world applications.

Not only this but often our method of configuration and / or implementation of the items or systems will be different due to our 12 years of vast technical knowledge and hands on real world experience with this technology as a specialist in this area.  This means that even just a voltage adjustment of say 0.4v difference (less than 1 volt) or even a temperature adjustment of just 5 degrees C can have a HUGE real world affect on whether you have an average result from your system or whether you have a great experience. 

If you think about it Solar Power Systems (making them work really well) have alot in common with baking a cake.  You could give 12 different people all the same ingredients and just depending on the way they put them together, the order they put them together, what settings are used for the mixer and oven etc and you end up with vastly different results.  The ones implemented poorly will FLOP and the ones implemented well will be amazing (yet in these cases the same $$ was spent on the ingredients), and this is the reality of the world we live in today.  One could even then say well the guy who had the flop now has to end up buying the ingredients again and wasting their time + energy to have a go a second time just to try and get the same good result that the other guy got the first time.  This is why often thinking you are saving a few bucks and up as a FALSE ECONOMY, as it ends up costing you more than to do it right from the start.  How many of you have ever watched Jamie Oliver on TV and thought that looks amazing what he's made, and you use the same ingredients and yet what you end up making turns out looking and tasting nothing like what you had seen him make?  If however you practiced and made the same thing 50 times over likely by the 50th attempt what you've made will be much better than the 1st attempt. The exact same is true for solar power systems and battery systems today except instead of $15-30 of cake mixture involved there's often $5000 - $90,000  dollars involved, so not something you want to be getting wrong and repeating.

With items we supply we are happy giving this correct technical advice / support away for free but only for items and systems we've supplied and we only give that advice / support away to the direct person or company we sold to, however with items supplied by other companies you cannot phone us up for free technical advice / support for items we have not directly sold or supplied you.  In turn we charge for technical support for anybody wanting technical advice / support for items or systems we did not directly supply and we may simply deny technical support for items purchased elsewhere also.

The real key point here though is that often a person may think that they're saving $40 or $60 buying what they thought was the same or similar item from a trading company, only to find that because of lack of advanced technical support / technical advice they end up with a poor experience that then means they're still unhappy with the result even after their purchase, yet if they had purchased through Hitek they wouldn't be in that same position and they would be assured of having a good experience and correct technical advice / support available.

Often when people are spending $2000 through to $90,000 then you really must think long and hard about what VALUE that advanced real world technical advice and technical support is actually worth to you if it means the difference between having a good long term experience from your hardware and your systems or having a poor experience from your hardware / systems and potentially replacing expensive items much sooner than expected.  Eg if you spent $4k on batteries and then you only got 2 years of life from the batteries as a result of running them in the wrong environment or with wrong settings then even if you thought you had saved $300 at time of purchase, you actually just cost yourself an extra $3700 after 2 years as a result of the consequences of that decision.

Buying and running solar items and solar systems is NOT like buying a new fridge from your local white-ware store.  With a fridge you basically just plug it in and away you go, you'll get the same experience no matter who plugs it in, but with batteries, inverters, solar panels, solar systems the same is NOT true at all, in fact it's very far away in real world reality.

With solar panels themselves they are rated as their "Peak Power Wattage" that only tells you what the panels will do during the best day of the year during the best part of the day (eg 12pm) on a clear sky sunny day during the peak of summer, however it does NOT tell you anything at all about how the panels will perform for you during a cloudy or overcast day, or during Autumn, Winter, Spring etc.  In turn our main focus with our solar panels has been real world NZ testing and NZ panel development right here in New Zealand to actually ensure our panels are tested back to back against other top brands of panels from around the world to ensure that our panels actually typically give HIGHER / BETTER real world power output in real NZ conditions than typical conventional panels.  In many cases back to back testing (including independent client feedback) has found that often many of our panels are able to give between 50% extra power per panel and often even up to 30% greater power (per rated panel watt) in real world NZ conditions.  This means we've had 1 of our 330w panels give up to 50% more power on a cloudy NZ day compared with a 1 year old 330w conventional panel supplied by another company.  Why this is critical is that for many system owners (including off-grid systems and RV's etc) the cloudy days are when you are needing that extra power the most, and so if a panel is only efficient at producing power in the peak of summer but terrible at producing power on a cloudy or overcast day then even though it may have the same Peak wattage label rating as our 330w panels that does not tell you anything about how similar (or dis-similar) the real world NZ power output will actually be between their panels vs our panels and in fact many companies in NZ have not even done ANY of their own real world back to back testing to even directly compare their panels vs other panels in real NZ conditions, and I can assure you just testing the comparison in China does not tell what or how they will perform like here in NZ as our atmosphere conditions are very different here.  It's well known that many panels designed for usage of solar power systems in China may run happily there for 10 years without issues and then as soon as those same panels are used here in NZ they may perform poorly or even fail after just 2-4 years, and people say why?  They don't understand that the panels need to be built to a different and higher (NZ specific) spec as our conditions here are very different, and this is exactly why we don't just import random panels and items from China and why we do our own development and testing of our panels and many items we supply to ensure the really will give a long life and best results here in real world NZ applications, but I'm not aware of any other companies in NZ that do this to the extent that we do.

Long story short, when you are buying your solar system or battery related hardware or items then you want to be dealing with a company who really cares about ensuring that each and every client ends up with a great real world experience, rather than a company who doesn't offer (or often even have the ability to offer) to advanced technical support to ensure you can even end up with a great experience because their primary concern is just making sales and lining their pockets (this is the opposite of what Hitek is about).

Our company slogan is "Empowering your world" as it's our goal with ALL of our systems to actually help  empower our customers, and part of this means being able to give them correct real world advice or technical support to ensure they can achieve a good experience, and this is our primary goal (not lining our pockets).

Because we are "Official" agents of the brands we use and supply then we get direct technical support and access to alot more advanced technical information than someone who is just grey market importing a brand and in turn is LOCKED OUT of the official manufacturer support channels.

I hope this article proves useful to really help people better understand why and how so many people can have bad or poor experiences just from buying hardware online from random sellers when in their mind they thought they were buying the same (or similar) items.  As the old saying goes "It's all in the detail" and when you don't even know what you are looking for in the first place, you don't know what correct questions to ask and in turn the critical details are often missed until it's too late and by that time you find out you have a poor experience and nobody there to properly assist you to get things running right for your site.

This is why we hear that around 80% of NZ solar systems running here in NZ today are giving LESS than optimal results or have not met the clients expectations or are not giving the power output or savings that a client had expected at the time of purchasing, yet for our clients and our systems we have amazing results and amazing success stories from the last 7500+ systems we've designed and supplied.

We have a saying that is "You don't buy Solar Panels or Batteries to just sit there and look pretty", meaning that unless they are doing their job and doing it well then there's no point on having them as if all they are doing is just sitting there looking pretty and not giving you good real world results and not giving you good real world savings then there's really little point having invested in them in the first place if they're not working well for you.

Many people don't realize that we actually DO have a price match policy*, which means if you do see the exact same make + model items as we are offering and it's in stock in NZ (currently in stock available) not coming on a shipment a few weeks away, and it's a public listed / advertised or quoted price that you can reference, then we are able to often match (or beat) that price under our price match policy.  What this means is that if you were thinking about buying elsewhere because you thought were were getting something slightly cheaper then PLEASE talk with us first and ask about this policy, as the very worst thing we can possibly come back to you saying is "sorry we can't help" but more often than not we may be able to come back to you saying "Congratulations" we can assist you with that.  There's a great saying "If you want something, it's best to ask", so we encourage our clients to please talk with us and at least ask us to allow us to best assist you rather than just assuming we may not be able to help you.

If you have an existing solar system (or battery system) that was purchased elsewhere or supplied by someone else that is not performing well for you or you are having constant issues then please feel free to give us a call and we will see how we are able to best assist you to help.




How much EXTRA POWER can PERC MONO Solar Panels produce compared with standard Mono / Poly panels? March 18 2017

Many people often assume (wrongly) that all solar panels are created equally, and they just base their decision (mostly) on the nameplate rating of a panel (eg a 250w panel), but as we can below in our own testing comparing standard 250w mono solar panels against latest 305w PERC MONO technology, this is not actually the case in the real world power output.

Using the world famous Tigo Energy panel level monitoring system to report the live power ratings for every panel on our site, we can clearly see that even though there's only a 55w / 22% nameplate difference in wattage between these panels, there's actually up to a 35% power output compared with a standard 250w mono / poly panel.  This actually ends up being 13% more power output than the nameplate rated difference as an advantage in terms of the REAL WORLD energy output from the PERC MONO panels during our own testing on our live test site in Mt Maunganui Tauranga (New Zealand). 

In the best cases we’ve even observed up to 50% more real world power output from our 305w PERC MONO panels compared with a standard 300w mono / poly panel during our NZ testing.  This translates to a difference of 3.5Amps output vs 7.5Amps output going into the clients battery on the same roof top when testing with 1 std panel vs one of our PERC MONO panels.

PERC MONO vs Mono / Poly Panel performance comparison

For people who care about the output of their on-grid, hybrid or off-grid system yearly output and especially their Winter, Autumn and Spring power production then PERC mono panels are certainly something well worth considering (even though they do cost a little more per panel) as they actually deliver some good real world efficiency gains (up to 13% more during our own testing) thanks to high efficiency latest technology cells with tiny mirror reflectors in the rear of the cells.

Typically the difference in cost is usually only around a small $80-110 cost extra (per panel), yet this extra cost often pays for itself within the first few years of running an off-grid system due to saving needing to run the generator for as many hours throughout the year.  Nowdays the solar panels themselves are actually one of the cheapest parts of a good solar power system, where as only 5 years ago the solar panels themselves were one of the largest costs of the entire system. 

Things such as alloy racking / mounting kit prices have stayed about the same and labour prices have actually increased, and everyone seems to be running out of good (un-shaded) roof top areas, so the real question is WHY would people want to waste their time, money and roof space installing low efficiency panels when once the "TRUE COSTS" are actually calculated it actually makes better sense to install latest technology higher efficiency panels in many cases.

One of our clients (Kevin in Kerikeri) had installed 12 x Hyundai 265w (3.48kW) of mono panels on his roof 1 year ago, and then this year he installed an additional 10 of our 290w (2.9kW) of our PERC MONO panels (on a different string so that the 2 sets of panels would not affect each other), and the 2.9kW of PERC MONO panels actually produced MORE power output each day even though there was 580watts less of panels installed. Yes before you ask all the panels were on the exact same roof top, facing the same orientation & tilt angle etc.  He was shocked with how much extra power the PERC MONO panels were producing for his site each day and he now felt that the existing MONO / POLY technology had now been "Outdated and Supersceeded by these new high efficiency PERC MONO panels".

Note: We have also ran the same tests on our 290w, 295w, 300w and 305w PERC MONO panels to also verify that they too show the same level of increased power production compared with standard panels, and yes all of our PERC MONO panels showed this additional power output.

For those of you who want to read up about the technology behind PERC MONO panels that help them achieve this extra output, then please read this article here:
  Why are high efficiency PERC MONO solar panels becoming popular?

The above link is well worth your 5 minutes of time spent reading through and you will learn alot.

Why Should I Consider Using Lead Carbon Batteries? May 05 2016

Lead-Carbon batteries are different from other types of batteries because they combine the high energy density of a battery and the high specific power of a super-capacitor in a single lower-cost device (also known as Pb-C).

Our Hitek Lead-Carbon batteries feature industry leading and proven technology, achieving maximum cycle life in a compact package.

The primary goals of lead-carbon battery research has been to extend the cycle life of existing AGM lead-acid batteries and also increase their storage capacity / power.  The Activated Nano-Carbon Enhanced negative electrode provides proven results and unmatched cycle life, even in a partial state of charge (PsoC) operation.  This is very beneficial in solar power systems, communication sites, Caravan, Marine, Motor-home / RV installations and many more applications.

We have pre-made battery racks available for our lead-carbon batteries to make installation quick and easy.  Our lead-carbon batteries are fully sealed Valve-Regulated and can operate on their front, side or standing upright to give you maximum installation options in any installation scenario.

Advantages of Lead Carbon compared with Lithium batteries and Lead-Acid:

* No BMS (Battery Management System) is needed to prevent over-charging and under-charging on a per cell basis, as lithium battery sets need.

* No thermal run-away risk of individual cells over heating, exploding and catching on fire as lithium batteries can have.

* Much better and greater kWh storage capacity per dollar compared with lithium (approximately twice the storage capacity from lead-carbon compared with lithium, or about half the price for the same kWh capacity).

* A nice easy to carry modular system where each battery can be carried and put in place 1 at a time, without needing any forklifts, jacks etc like you need to install the Tesla Powerwall battery and Panasonic Lithium Home Storage Battery.

* Suitable for On-Grid Hybrid and Off-Grid systems due to high discharge amperage capacity.  A set of our 14.4kWh lead-carbon batteries is capable of 5kW discharge capacity without any problems or issues, yet lithium batteries such as the Panasonic Home Storage Battery + the Tesla Power Wall battery are limited to 2 - 3.3kW constant power output which in turn makes them un-suitable for off-grid installations.

* No Cooling fans / system is needed for lead-carbon batteries, yet lithium batteries such as the Panasonic Home Storage Battery + the Tesla Power Wall battery need active fan cooling to constantly regulate and keep the lithium battery temperature cool otherwise over-heating and risk of fire / explosion may result if they had a cooling system failure.

* Can easily retrofit / retro-fit onto ANY / ALL existing systems running existing lead-acid batteries, where as lithium batteries can't easily be added onto existing older systems that are running older lead-acid batteries.  In turn our lead carbon batteries can work on older systems that may be running Outback Power, Midnite Solar, SMA Sunny Boy / Sunny Island setups, Enasolar, Enphase, APS, Solax, Goodwe, EP Solar Tracer, Xantrex, Schneider, and many other existing older system types.

* Much higher energy density and longer life in the same size (or smaller) package compared with existing AGM / GEL and Flooded Lead Acid Batteries.  Eg a typical 6v Crown / Trojan 430Ah L16 style Flooded Lead Acid Battery only gives 1200 cycles at 50% DOD while our lead-carbon batteries offer 3500+ cycles at 50% DOD while also giving MORE usable Ah / kWh storage capacity at the same time.

* No need to run lots of separate 2v batteries as was the norm with older lead-acid solar storage setups, as our 6v 300Ah battery sets offer much better value for money per kWh than existing traditional 2v setups offer, however yes we can also offer our lead-carbon batteries as 2v battery versions also (via pre-order only).  This not only saves you money but also means our battery storage system offers a much faster and easier installation in comparison.

* High Amperage Charge & Discharge capacity compared with Solar GEL batteries which have low charge / discharge amp input and output current restrictions.

* No harmful and toxic gases coming off our lead-carbon batteries (as they're sealed), so you don't have to worry about terminals and wiring corrosion, or spillage of liquid acid, checking fluid levels, hydrometer checking and all the safety risks / hazards that you have with existing flooded lead acid batteries.  Our lead-carbon batteries don't need external outdoor ventilation as normal lead-acid batteries do.

* Up to 20 Year Design Life for our lead-carbon batteries (when running in best case with perfect environment conditions), compared with standard lead-acid batteries that have a 3-5 year design life and lithium that has up to 10 year design life.

We have now supplied and deployed more than 7,500 of our lead-carbon batteries to clients around NZ and also international clients all around the world (as at 2019), and we've not had a single client who has not been happy with how nicely the lead carbon batteries are running for them on their solar systems.  Many of these clients previously had existing lead-acid batteries that had failed on them much sooner than they had expected and they wanted a more reliable long-term solution.  Our lead carbon batteries are the answer and today here in New Zealand we've not found another single solar / energy storage battery that is "Better Value for Money" than our lead-carbon batteries when usable battery life and usable energy storage are part of the calculation.

Note: We can offer wholesale / trade supply to other companies who may wish to offer our lead-carbon battery storage options to their own clients.  Please contact us for more information.

Latest Technology Update for Solar Power and Energy Storage Options in NZ October 11 2015

Having just returned back to NZ from attending the latest All Energy Solar Power Expo in Melbourne Australia, we are very excited and proud to be able to advise clients that our Solar Power Solutions really are cutting edge, using only the best and latest technology from around the world.  From our assessments our solutions we offer today are about 1-2 years ahead of what most other typical NZ Solar Power Companies and your average electrician are able to offer.

 Listed below are some of the latest solar technology highlights that many kiwis here in NZ are eager to learn more about.

1. The Enphase AC battery

What is this and why do I want or need it?
For anybody here in NZ today (plus Australia and other countries) that runs a solar power system using Enphase micro inverters (mounted on the rear of your panels or on the rail behind your panels) you've had no option to easily add on a battery / energy storage solution.  Enphase have realised this so have been working on a battery solution for these millions of customers around the world, and it will be available in July 2016 next year.

This sounds great so what are the estimated costs and any pros / cons etc compared to other options?
Aside from the fact that this battery is 9 months away from being available, it is only a tiny 1.2kW hours worth of battery storage capacity.

To put this into perspective the average Kiwi home uses around 8-10kW worth of power per evening (from 6pm – 8am) so with this in mind the average NZ home would need around 6-7 of these units (running together in parallel) to give enough storage capacity to get through most evenings without drawing power from the grid. At this stage indicative pricing is estimated to be around $3000 Inc GST (NZD) per unit inc installation. However lets just assume that if you were buying 6 of these units together and getting them all installed at the same time that the pricing might drop to $2800 per unit x 6 = $16800 for 7.2kW hours of storage or $19,600 for 8.4kW hours of storage. If we compare this against our current latest Lead Carbon Supercapacitor battery setup which offers 14.4kW worth of storage (essentially twice as much) for around $14,500 including installation (as a retro-fit option for any clients with existing Solar Power systems) then we can see that the Enphase AC Battery option doesn’t actually stack up good for those people who are needing 7-14kW worth of storage each evening. Even if you were only needing 6kW worth of storage per evening the Enphase AC Battery option is still expensive for the small amount of storage capacity that it offers.

Note: For any clients with a Renesola or APS micro inverter setup (or even an Enphase, Enasolar, SMA, Samil or other inverter setup) our Retro-Fit option can bolt on and happily work with All of those existing On-Grid systems.

2. The Tesla Powerwall 7kW Daily Cycle Battery (Also known as 7kW Tesla Power Wall).

What is this and why do I want or need it?

Tesla (the electric car maker who makes the famous Model S cars and Model X SUV) have partnered with Panasonic to make their battery “Gigafactory”. They are building high volumes of 18650 lithium cells and using these in their cars and have now also just started packing these into their Powerwall product for clients with solar power systems to give them an option of storing their excess energy produced during the day for use in the evenings. Currently the only NZ partner that Tesla have formed an agreement with here is Vector Energy in Auckland, however typically Vectors model means that they install the system in your home and they own the system and you simply get a slightly reduced power rate (per kW unit) for the 10-15 year agreement period that you sign into. The advantage with this is that you never pay an upfront cost for the system, however the downside is that they own the system and you never reach that point where you are now getting “FREE POWER” from your system. They’re essentially using your roof space to generate power for their network and also selling this FREE Power back to you at a slightly better than average price compared to what other homes are paying from most other power companies. This can give some clients the FEEL GOOD factor of having a solar power system on their roof, however in our opinion it also never gives you quite the same feeling as when you know you truly have “FREE POWER” for the next 10-20 years like you do with our Solar Power Systems / Hybrid Systems that you pay upfront for and then they pay themselves back until the point where they now no longer owe you anything and all power produced is free for you to use however you like.

What are the estimated costs and any pros / cons etc compared to other options?
Aside from the fact that this battery it 6 months away from being available from Vector and they will own the systems they install at your home, there will be other companies offering the Powerwall battery with their own Solar Power Systems, however right now Fronius (one of the announced Tesla partners) is still 1 year away before it will have a compatible single phase inverter available for the NZ market (with certification) and even once this is available it will end up being an expensive solution for only 7kW hours worth of battery storage capacity.

To put this into perspective the average Kiwi home uses around 8-10kW worth of power per evening (from 6pm – 8am) so with this in mind the average NZ home would need around 6-7 of these units (running together in parallel) to give enough storage capacity to get through most evenings without drawing power from the grid. At this stage indicative pricing is estimated to be around $15,500 Inc GST (NZD) per 7kW unit inc installation and the Fronius Inverter setup (excluding any solar panels etc, we’re just talking about upgrading an existing installation here). If we compare this against our current latest Lead Carbon SuperCapacitor battery setup which offers 14.4kW worth of storage (essentially twice as much) for around $14,500 including installation (as a retro-fit option for any clients with existing Solar Power systems) then we can see that the Tesla Powerwall Battery option doesn’t actually stack up good for those people who are needing 8-14kW worth of storage each evening. Even if you were only needing 6-7kW worth of storage per evening the Powerwall Battery option is still expensive for the small amount of storage capacity that it offers and considering it’s going to be at least 1 year away before the compatible Fronius Inverter will be able to bundle with it for use here in NZ (if you were wanting to buy the system outright, rather than go down the track of Vector owning your system as mentioned above).

Note: For any clients with a Renesola or APS micro inverter setup (or even an Enphase and other inverter setups) the Tesla Powerwall battery setup will not easily or simply add onto your Micro Inverter system setup, however our 14.4kW Lead Carbon SuperCapacitor Retro-Fit option can bolt on and happily work with All of those existing On-Grid systems.

3. Lead Carbon SuperCapacitor Battery Setups (Also known as PbC or Pb-C or Lead Carbon Batteries).

What is this and why do I want or need it?

This technology has been worked on for more than a decade by some of the largest battery manufacturers around the world and finally it was announced last year that a couple of these companies had succeeded in having products ready and available for the Solar Power Storage worldwide market. Essentially this technology takes the existing technology of the best AGM (Absorbant Glass Matt) and GEL battery technologies, and gets rid of the standard negative lead plates within these batteries (which are prone to sulphation after even just a few years of heavy deep cycle application usage) and instead the negative plates are replaced by Activated Carbon SuperCapacitor plates which in turn is much more robust and more resistant to sulphation in comparison and can handle extreme heavy duty cycling and even 100% discharging frequently without the battery going bad or degrading like a normal AGM / GEL / Deep Cycle Flooded Lead Acid battery would. Currently there’s only a couple of top manufacturers in the world with this technology available for the public to buy, but within the next few years this technology could and likely will replace most standard car batteries, most solar power storage batteries, ups batteries, marine batteries, forklift batteries etc because it’s not much more expensive in comparison but typically offers 3 x the usable life span (without requiring water / fluid top ups or regular cell hydrometer checks etc like flooded lead acid batteries do). One other advantage is that is virtually produces no gassing while charging / discharging, so you don’t have the same dangers or hazards as you would when you are using flooded lead acid batteries, these are a lot safer for homes, motor homes, batches, cabins, the work place, etc.

What are the estimated costs and any pros / cons etc compared to other options?
Typically the costs compared with a good quality AGM / GEL Deep Cycle battery is around 30-50% more cost, however remember that most Lead Carbon SuperCapacitor batteries can be used to 80% and even 100% DOD (Depth of Discharge) and still give 3x the cycle life of these existing older technology batteries. So if you had a 6v 400Ah AGM battery vs a 6v 300Ah Lead Carbon battery the 400Ah AGM would give you 1.2kW hours of storage per battery for around 600 cycles, while the 300Ah Lead Carbon battery would give you around 1.8kW hours of storage per battery for around 1500 cycles. So as you can see much more cycles and a much larger amount of usable energy storage. One of the downsides with Lead Carbon batteries is that they are quite heavy, typically around 31Kg for a 12v 70Ah and around 61Kg for a 6v 300Ah, so by the time you have 8 of the 6v 300Ah batteries then you are basically at around 500Kg of weight (so not something that you’d want to be moving around once it’s installed and running). This means that this is great for Solar Power Stationary Storage but not as good for use in Electric Cars (EV cars) where Lithium is better suited due to it being much lighter which is a benefit in cars.

Value for money though however for Solar Power Storage Lead Carbon SuperCapacitor batteries can offer between 1500-6000 cycles (up to 10 years worth of usable storage) for a very good price, without the risks and dangers that you have with Lithium storage today. Essentially Lithium storage requires a good BMS (Battery Management System) to balance and manage each cell, as any cells that get over or under charged / discharged can catch fire and explode if not well managed, however these “Thermal Runaway Events” are not a problem for Lead Carbon batteries (which can also be easily retro fitted into most existing systems that use any Lead Acid / AGM / GEL battery setup today).

Why doesn’t my local battery shop / store or local Solar Power Company advise or tell me about these new options?
That is a good question and it mostly comes down to the fact that many of these companies may likely not be aware of this new technology or even have access to this new technology from their existing suppliers or battery companies that they deal with. Remember also that battery shops are in the business of selling batteries and so if you have to go back to them every 3-4 years for a new set of batteries then this is very GOOD business for them as then you are a repeat customer. If they were selling you a battery setup that lasted you 10 years then that wouldn’t actually be very good for their business as then they wouldn’t have many repeat customers coming back and so in some cases they may have to change their business model or face going out of business (similar to what happened the many video stores once Netflicks became popular offering streaming movies, nobody wanted to hire DVDs anymore and most of the stores closed).

Can these new batteries be used for On-Grid, Off-Grid and Hybrid Setups?
Yes correct, they can be used for all of those setups whether you want to self-consume your own stored energy each night and charge up FREE from your Solar Power setup during the day and simply have the grid there as a backup (this is called an On-Grid Hybrid) or whether you want to go completely Off-Grid and produce, use and store 100% of all your own power each day, and simply have a backup generator available for when you get multiple bad stormy grey sky days in a row (especially during winter) this is called an Off-Grid setup, these new batteries can be used for any and all of these different setups and even Wind Power / Hydro Power setups also (for people who may have these instead of or in conjunction with Solar Power setups).  In fact we have already supplied many on-grid hybrid and off-grid setups to clients already this year using this latest technology, and EVERY single customer running this technology is very happy with how well their system is running and the savings it is giving them in turn.

4. Shade Tolerant / Shade Optimized Solar Panels

What is this and why do I want or need it?
Are you talking about Micro Inverters like Enphase, APS and other companies offer right?
Actually sorry, no we’re not. DC Optimizers and in particular Smart Panels are not panels that have a small Micro Inverter bolted onto the back which then outputs AC power (as the micro inverter setups do) but instead these Smart Panels are a much better, sleeker and more refined solution and these panels continue to offer DC output just like normal solar panels do.

Traditionally normal Solar Panels were not great at handling situations where 1 or more panels on a string of panels were troubled by some part or total shading situations. With panels connected in series the output of all the other panels was ONLY as good as the lowest performing panel, so if you had 10 x 250w panels and 9 of these are giving 240w output but one is part shaded and only giving 100w output, then essentially your other 9 panels are losing 140w worth of output for each panel which would mean that your total output would only be 1.24kW of power instead of 2.4kW worth of power, so essentially we would half lost close to half of our power output for all the panels on that string. The situation would even become worse if there were 1-2 panels which were 90% or 100% shaded, as then the output of each panel may drop down as low as 40w each in the same example which means you’d have huge losses and then your system wouldn’t be producing the power that you are needing it to and paid for it to be producing when you purchased the system.

With Smart Panels or DC Optimized panels you essentially have an automatic bypass path open up so any panels which are shaded the power instead of getting stuck at those panels (like a road block slowing down traffic) can just go around the blockage without decreasing the output of the other panels.

What are the estimated costs and any pros / cons etc compared to other options?
There are 2-3 different ways you can get this new technology.

You can either buy “Optimized / Smart panels” which already have the optimizer module / technology built into or clipped into the rear of the panel (only for panels built on Tigo TS4 platform Junction Boxes) or for other panels from other vendors that may be older or not up with this new technology then you will be able to buy a retro-fit external box that simply plugs into your modules that are suffering from shading. The good news with this technology is that you do NOT have to install / upgrade every panel to be “OPTIMIZED” but rather just the panels that are suffering from shading. As a bonus any optimized panels can also have a wireless gateway unit setup to communicate with them if you want panel level monitoring available to see the output of each panel on your laptop, PC or smart phone (however that’s an added cost for the Wireless Gateway setup and is not needed for the Shade Optimization setup). The typical cost extra per panel for it to be Shade Optimized (as a Smart Panel) is around $130-160 per panel, so not really a lot of cost for the benefits that this technology offers, of course spending this cost on a low wattage panel such as a 140w panel would not be as smart as spending this cost on a high wattage output panel such as a 265w panel, as the optimizer costs are the same for both panels. If you look at the cost per micro inverter of around $260-300 per micro inverter (per panel) and needing to spend this cost for every panel on the string (rather than just those you want to be shade tolerant) then the micro inverter option ends up MUCH more costly in comparison especially on setups with 14-28+ panel setups compared with this new Tigo Smart Panel technology.


Why doesn’t my local electrician or Solar Power Company advise or tell me about these new options?
That is a good question and it mostly comes down to the fact that many of these companies may likely not be aware of this new technology or even have access to it from their manufacturers / suppliers they deal with. In time, likely 2-4 years from now this technology will become mainstream and likely standard with many new panels in the future, but for now this will ONLY be an upgrade offered by a few Solar Power companies in NZ who offer the LATEST technology to their customers. Some Solar Power Companies and Electricians do NOT like change and they may not properly understand or appreciate this new technology or want to re-train to be able to offer this to their clients. Sometimes it’s easier for them to just stay offering the existing older solutions that they know and are comfortable with instead.

Please note that the information shared and expressed here is simply the opinion and views of Hitek Solar NZ, however we do try and get the information and facts as accurate and correct as possible to best help all of our clients to become better educated and to help with their future decisions. For those Electricians, Solar Power companies and even RV / Motor home companies around that do NOT offer this latest technology, but would like to have access to it then feel free to contact us as we also offer wholesale supply to many other companies around NZ. Please excuse any typos also thanks.

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