News

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.


Disclaimer:
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.

If you want to know more information about any topics or items mentioned, please fill out the CONTACT form here on the website so we can get in touch with you thanks.