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Off Grid And Battery System

BECOME BOSS OF YOUR OWN SOLAR POWER
And disconnect from the net as you please…

Javac has been studying a hybrid solution for alternative energy for 2 years now, when the news came about the imminent blackouts, the requests from our clientele come back like clockwork, every time doomsday messages appear in the press, the idea of a blackout, on the one hand, just think of the dentist, or villa owners with an alarm system, or almost all of us with central heating, this can lead to life-threatening situations, especially for older people.
On the other hand, the unease of electricity that is becoming more and more expensive due to all kinds of surcharges, transport costs, etc., where we have not yet seen the end.
Below you can read how the placement of a Javac Edge Powerbank, whether or not connected to a PV installation or generator, can take away a large part of these worries.

The Current Situation in Belgium,
Belgium itself produces far too little energy to operate industry and heating systems in the winter.
Belgium is therefore dependent on the surpluses available abroad.
These surpluses are purchased at a high price, driving up prices.
It can even come to the point that we cannot buy enough energy from abroad, which can lead to a power shortage with all the consequences that entails.
Even if there are sufficient surpluses abroad, we cannot transport that amount of energy to Belgium via the existing high-voltage grids.
Due to a limited capacity on the cables. In the first phase of shortages, zones will be disconnected from the power grid for 4 hours, resulting in all possible problems.
Switching off and switching on such a large number of consumers carries a high risk of gigantic peaks and can cause further consequences.
This could lead to even larger areas without electricity for much longer periods.

What are the obstacles on the Belgian market for a massive switch to battery storage?

1. Does it make sense to install a battery to take advantage of nightly rates?
Most electricity suppliers in Belgium currently offer a day and night tariff.
Electricity costs about 6 euro cents per kWh more during the day than at night.
For an average family that annually consumes 1600 kWh at day rate and 1900 kWh at night rate, a battery can reduce daytime consumption to 0 kWh.
At night electricity is taken from the grid to charge the battery and during the day the battery supplies the necessary energy.
The entire consumption of the family is then billed at night rate.
By using the battery, the family saves 96 euros per year on the bill, which is far too little to earn back the batteries.
Perhaps in the future smart meters will make it possible to earn enough money from batteries.
One can then opt for an hourly rate instead of day and night, which means that the price differences are greater.

2. Obsolete power grid as free battery
To start with, Belgium needs a smart grid to get more out of our PV installations.
The situation in Belgium is complicated and complex.
We are stuck with different nets & network operators in Flanders, Brussels & Wallonia.
But above all, the grid itself already functions as a free battery.
Indeed, the old electricity meters that are still often present count back to zero if we produce more solar power than we consume.

3. Need for ‘smart meters’
Supplying back to the grid was free, but that has changed in 2020.
This means that we will owe energy taxes on the electricity we have generated ourselves and temporarily put on the grid.
Now that is not yet the case. Parking our solar power on the grid will then no longer be free.
Since 2020 there are smart meters.
They themselves send the data about your consumption and could, for example, search for the best time and the best rate to regulate your home consumption.
But the big advantage of a free battery will soon disappear from the picture.

4.. New rate structure needed
In Belgium there is also no tariff that encourages people to install battery systems.
In 2017, VREG will completely review its distribution tariff.
This will probably result in the tipping point for transferring residual electricity from batteries to the grid.

5. Affordability?
The good news is that prices are falling continuously.
This lower price is not so much made possible by innovation, but rather by capitalizing on economies of scale.
After all, the lithium-ion battery is something that has been used for some time in mobile applications such as smartphones and laptops.
In America and China, a few giga-factories are on the rise, the result will be that an enormous volume of batteries will be produced.
The Javac Edge Powerbank will already largely neutralize the threshold of the heavy investment, due to its current price of an 11.4 KW powerbank, so that the payback time is considerably shortened, and with a technology that is optimally adjusted to solar panels.

6. Technical regulation not yet very clear
Once on point, a lot is possible with the Javac Edge Powerbank, a battery system can quickly make the difference. Without batteries, your current self-consumption of solar power is about 30%.
That can evolve to 95% provided a battery of 11.4 KW for an average household.
The further the cost price of the storage systems decreases, the more return can be achieved from your system.

7. The question is when to get in?
Wait for further price falls and in the meantime swallow the loss of yield or wait for your investment to fall, assuming that it falls, of course, because raw materials worldwide have recently started an upward movement, and interest rates are now also rising.
If you already have solar panels, and you already have a smart consumption meter, then you have absolutely no reason to postpone this investment, the payback effects may already have been achieved after 2 years, the protection against blackout is included for free, if you also provide a small Nanomag generator NM-7500 A or B, a disconnection from the grid gives you a big financial advantage.
If you have not yet invested in solar panels or a wind turbine, the combination with the Javac Power Edge bank could be just that push to take the step towards avoiding increasingly expensive electricity bills.
You can wait until the prices of the batteries drop even further, that is quite possible, even desirable, but in the meantime the prices of power consumption are increasing at a crescendo, together with the distribution costs and all sorts of taxes, this bill is gradually becoming a noose for many households , and SMEs.
This battery, in combination with a relatively small generator and/or solar panels, certainly makes you less dependent on the ever-increasing bills from your grid operator.

What does the future hold for energy storage?
Off-gridd solar energy is making a comeback, until now whether or not to charge for the electricity infrastructure has been a purely academic question, but that could change, as it seems that local storage using batteries is becoming an makes a comeback by launching the Javac Power Edge Powerbank.
The life4PO batteries are superior to the lead-acid batteries that are traditionally used for off-grid solar energy.
They last longer, are more compact, more efficient, easier to maintain and relatively more sustainable.
There are other factors that play into the hands of home energy storage.
In many European countries, financial incentives for grid-connected solar installations have now been removed.
The electricity companies have successfully challenged these financial incentives, arguing that solar panel owners use the electricity infrastructure but do not pay for it, increasing the cost to other customers.
The irony is that energy storage at home can become more financially attractive by installing intellectual energy meters than connecting a solar installation to the electricity grid.
As a result, the electricity companies could achieve the opposite of what they want.
They then lose even more customers, so that the costs of the infrastructure have to be borne by fewer and fewer customers, so that more and more people switch to an off-grid system, and so on.
If we also take into account the difference in lifespan, the advantage of a Javac Edge Powerbank becomes even greater.
If we assume a lifespan of 20 years for the solar cells and a DoD of 80% for the batteries, the Javac Edge Powerbank will last about as long as your solar panels.
In contrast, lead-acid batteries need to be replaced two to four times over those 20 years.
This makes the advantage of a Javac Edge Powerbank over a lead-acid battery even greater.

Why store solar power?

A storage system makes it possible to shift the consumption of solar power from the time of production during the day to a later time in the evening or at night.
This has advantages both for the consumer himself and for the management of the electricity grid.
By (partially) storing solar power, less power is injected into the grid at times of low consumption.
This reduces the imbalance that must be compensated by the network operator.
After all, most solar power is generated around noon at the highest position of the sun.
But then household consumption is also the lowest.
Moreover, the consumer can use a larger share of his self-produced power himself, which is interesting if there is a tariff difference between his own internal consumption and supply to the grid.
An additional smart control can also intelligently control household appliances by switching them on automatically at appropriate times.
This is only possible with smart devices.
The active demand control of the energy management system also relieves the batteries and extends their service life.

Can existing PV installations be adapted for emergency power supply?
Existing PV installations can be expanded with various modules for storage, intelligent energy management and an emergency power system.
There is a freedom of choice regarding the type, number and capacity of the batteries.

Consequences of power failure
– No lighting
– No heating (controls no longer work, even with many wood stoves)
– No hot food
– No cooling in freezer and refrigerator
– No mobile phone, PC, TV, …
– Electric gates and fences no longer work
– No alarm systems and protections
– And so many more things don’t work anymore, a long list of serious inconveniences that we don’t always think about.

Practical case in the event of a power failure
If this happens for a few hours or just one day, it will already cause a lot of problems.
After a few days it gets really chaotic and the consequences can be very far-reaching.
For those who do not have solar panels, such as people who live in an apartment and where an emergency power generator is not possible for practical reasons, the solution is the Javac Power Edge to properly bridge a blackout.
But with solar panels you are not there yet.
There are more than 300,000 installations of solar panels in our country, but these will not work since all these installations must be connected to the power grid in order to work, unless with the Javac Power Edge.
If the batteries provide enough power to keep the inverter of the solar installation working, you can immediately use the power you generate and use the surplus to charge your batteries.
If you then have enough power in the batteries, you can already talk about basic comfort.
This is also a very interesting application for companies.
Every company has experienced a power outage that has left staff unable to do their job.
As soon as the UPS systems turn off the computers and servers, the heart of the company is paralyzed, so if you have VOIP, the phone is also dead.
This entails many direct and indirect costs.
The Javac Power Edge keeps computers and controls working.
The staff can then continue to work on the computers and servers.
Of course, major cuts must be made on unnecessary consumers in order to make optimal use of the batteries and/or solar panels, because this energy is of course not endlessly available.

How about a generator? But make the right choice
A generator, as an emergency power supply, works well but with several drawbacks.
As long as you have fuel, you will have power, but if it runs out, you will also be without it.
During a blackout, the petrol stations will not work either.
Further disadvantages are of course the noise and the emission of exhaust gases.
If everyone outside turns on an emergency generator, this will certainly cause a lot of inconvenience to people and the environment.
If the generator is not equipped with an (expensive) network takeover or ATS, inexperienced people will connect several devices to the power group themselves with extension cables.
In most houses there are still old, repaired or too thin extension cables that will melt if the power is too high.
If too much is connected, the safety devices of the generator can blow, if it is already equipped with one.
The air-cooled 3000 tmp generators are also not made to run in 24/24 7/7 mode and can overheat and even jam.
But suppose you are a handy DIYer and you connect your generator to your distribution board, without an ATS system, the consequences can be incalculable.
In the beginning there will be no problem.
As long as the grid is out, the necessary circuits will be supplied with electricity from the emergency generator.
What will happen when the grid comes back on and the generator is connected to the grid?
Any generator that is connected to the grid has to synchronize with the grid before being connected and that never happens on the small generators on the market.
If you simply connect an emergency group to the grid, you can cause enormous currents when the electricity grid returns and all fuses would blow.
This can have further consequences for everything that is connected in your home, but also for the power grid itself.
And then we haven’t even mentioned the quality of the output of your generator, your sine wave and Hz are extremely unstable, watch out for all electronics, alarm systems, switched central heating pumps, even a simple Espresso coffee maker will refuse to work.
Only 1 device is eligible for this and that is the Javac Nanomag NM-7500 A or B, great advantage of this generator is that the output is even better than this infinite of the grid.
This technology is also available in powers up to 75 KW and coupled in series, it can provide the largest consumers with the final solution when protecting installations that feed high-tech installations (server rooms, data storage, medical and nuclear sector).

OR BETTER A JAVAC EDGE POWERBANK?
The hybrid solution with a battery pack has gained momentum in recent years.
Javac did not miss this opportunity and launched its Javac Egde Powerbank in various capacities at the beginning of 2017.
The formidable possibilities can hardly be overestimated, but much more is possible with such a battery system.
Today you can only use electricity from your PV installation if you use the generated power at the same time.
But when are you usually home?
Right, when the sun is (almost) gone.
So your power peak at noon simply flows into the public grid.
And conversely, you have to take power from the grid when it is cloudy or dark outside.
With batteries, you can better manage your own solar power production, for example by saving the power for the evening.
That in turn illuminates the net, because the peak shifts.
And that can ensure that electricity prices fluctuate less, and it can even go further.
For example, you could develop a system that predicts your production and consumption based on the weather forecasts. This way you can optimally charge and discharge your battery. The Javac egde power bank is a progressive battery pack, with capacities available as standard from 6 KW to 24 KW, but also mega capacities of + 100 KW for industrial applications. The energy that is stored from solar panels, emergency power generator, windmill, watermill, or even from the ordinary grid, coupled, with an intellectual inverter (CMS) ensures that the most economical power supply is always used. The Javac Edge Powerbank can be hung on the wall if desired, or provided in a cabinet that requires only a small mounting space. With a power of 11.4 KW and a weight of only 140 kg, for the most common javac power edge bank it is easy to find a place in the building with a high efficiency of eg +2000 load cycles at 80% and much more at lower depth charges , this battery will continue to deliver its power for 99.9%, and this for + 20 years with a warranty that extends to 10 years, subject to compliance with the warranty conditions.

BUT THE BEST SOLUTION = PV +POWERBANK + GENERATOR

From 1 July 2016, the distribution system operator Eandis introduced the prosumer tariff, which is the first step towards making solar panel owners more responsible. This means that anyone who connects solar panels to the grid must pay a fee of 62.9 to 83.99 euros per unit of installed capacity (kVA). For an average family that provides its own energy with solar panels, that is an amount between 250 and 500 euros. Per year. You do not have to pay this amount without a network connection. Going off-grid means you will maintain your own 50 hertz network. Therefore, at any time, the consumption of your household appliances must be equal to the production of the solar panels or reserve in the batteries. With the javac edge power bank of 11.4 KW, it is already more natural to meet the needs of the family at any time. Even if you simultaneously have two hotplates, the dishwasher and the dryer on while your daughter dries her hair, you will rarely be short of power in the summer months, at least when the sun is out. In the winter period when the sun is lower, and there is a greater chance of dark weather, a small Nanomag generator of 6 KW will be the solution to make up for these shortages, also because this generator consumes only 0.8 lt./minute, and thanks to its Nanomag technology fully charges the javac edge power bank in less than 2 hours (cost = 2 x 0.8 liter fuel at 0.40 cents/litre = less than 1 euro for 10 kW, via
your network administrator has lost you 4 euros, and tomorrow even more
Belgium doesn’t have many remote locations, although you would be surprised to see the number of households living without electricity in remote chalets. And who have chosen to go off-grid out of financial necessity or principle. Also because many of these accommodations, like so many holiday homes in the Ardennes, and in wooded areas do not have an electricity connection. You will also find extensive areas in our southern neighbors where there is little or no reliable electricity network. We can also question the reliability of the Belgian grid in the coming years. A harsh winter can still bring a rolling blackout. Using the batteries as a backup makes sense in that sense. If all goes well and the combination of solar energy and a power bank becomes a commercial alternative to traditional energy suppliers, the current market model will be completely turned upside down. In this way, the combination of PV generator and Java Edge power bank could indeed be the missing piece to bring a sustainable energy supply one step closer. And here it is gradually becoming clear that you might get the naughty thought to suddenly go off-gridd, indeed now it can become advantageous to provide your own energy without a network connection with solar panels and batteries with a small generator of 6 kW.

SUMMARIZED: WHY THIS JAVAC SOLUTION?
• Approximately 57% less electricity needed from energy companies
• Possible to use solar power all day long
• Can work as a back-up system if the electricity grid were to fail. Almost all of the annually generated solar power is consumed.
• Possible with almost every existing solar power installation
• Ready for the future with Smart Gridd compatibility
• The Javac edge power bank energy storage system with dc coupling uses a battery to store or consume electricity when needed.
• To optimize self-consumption, the battery is automatically charged and discharged depending on consumption needs. In this way, the energy supplied by the grid is kept as low as possible.
• Provided that the combination PV installation/generator/power bank disconnection from the grid is no longer an illusion

THE CONTROL OF THE JAVAC EDGE POWERBANK

The intelligent inverter of the javac edge power bank consists of an innovative battery manager (BMS) combined in a single unit and optimizes the self-consumption of your solar energy. It manages the energy balance using self-generated solar energy, and immediately stores all unused energy in batteries for later use. Traditional PV systems without energy storage produce only 20% of the directly generated solar energy for self-consumption. The unique CMS is the heart of your optimized self-consumption system. It is a compact, all-in-one device that manages your solar panels, batteries, electrical appliances and grid connection, just like a power station. Fully automatic! Increase solar energy self-consumption many times over by using the javac CMS controller connected to your javac power edge up to +90%. The main benefits: greater independence from energy suppliers and rising energy rates, sustainable energy use and greater savings. By supporting the principle of energy storage with the JAVAC CMS, you confess color. You opt for green intelligence and the great benefits of sustainable energy. And one thing is certain: you will love it. The technology, the independence, the savings, the sustainability. Future-proof, sustainable and intelligent. You can start generating solar energy, with battery storage making you largely independent of your energy supplier, or you can upgrade your current PV system to a full-fledged energy storage system. It enables user-friendly monitoring, analysis and control of the system. Anywhere in the world.

How does the Javac edge power bank differ from other battery systems?
The Javac edge power bank from the Lithium class (LiFePo4) testifies to the most eye-catching and extreme lifespan; after 2000 intense deep discharge/charge cycles, 80% of the original capacity is still present. With shallower discharges, this number shoots up sharply. Things that affect the life of all batteries are temperature (high ambient temperatures are to be avoided, the average depth of discharge and how heavily they are loaded in terms of incoming and outgoing currents as a back-up to the regular power grid against power failures, or for daily use.The long lifespan (>5 times GEL/AGM) translates into low TCO (Total Cost of Ownership); although the purchase is more expensive than the lead-acid batteries, the final costs are much lower.The LiFE4PO technology also distinguishes itself in its charging protocol. A lead battery, for example, may not be discharged further than 50% of its specified capacity for an optimal lifespan. Moreover, charging must always take place in one go to 100% SOC. That is, if you exceed the 500 cycles (optimal lifespan) ) with solar panels, this is particularly difficult if the sun fails at 75% SOC. This shortens the lifespan dramatically. The Javac edge power bank is not affected by this at all, you charge the battery when and how much you want and when the opportunity arises and through the medium where the CMS controller decides, either solar panels, or a generator, or the grid. Partial or full charge cycle. The javac edge power bank also has a linear charging curve, which means that it recharges very quickly. The charging curve for the lead battery flattens out, so that 10-12 hours are always required. As a result, solar panels cannot be used optimally; even if they generate 20A charging current, this does not mean that the lead battery will absorb that current, making it difficult to charge the battery, even on a sunny day.
In fact, the solar panels could be smaller for the same yield or, the battery will be fuller on average. A charging current is not fully absorbed by a lead battery, a loss of 15% (especially with an older battery) is not unusual; 15% of solar power is lost… our javac edge power bank 99.9% effective.

OPERATION OF THE VARIOUS BATTERIES, AND THEIR PROPERTIES?
Lead-acid battery. These batteries are similar to the starter batteries in cars. This technology is mature and the batteries are relatively cheap. A disadvantage is that you should not discharge them completely because they will be damaged. Usually they are only discharged to half. As a result, the installed battery capacity must be twice as large as the actual energy storage capacity you need. Another disadvantage is that most of these batteries can only handle a few hundred to a maximum of 2000 cycles. If you assume that you charge and discharge the battery once a day, you will arrive at around 250 cycles per year in Belgium (because there are days with little or no PV yield). A service life of 2000 cycles then corresponds to 8 years. This means that you will probably have to replace the battery once during the life of the installation. There are special versions for the storage of renewable energy (solar versions). These can better withstand periods when the battery is not fully charged.

Lithium-ion batteries. These batteries are also used in electric vehicles and mobile devices such as laptops and cell phones. The high energy density of this type is an advantage for these applications. That means smaller and lighter batteries. This is less important for integration in buildings, but because the batteries are used a lot, they are also available relatively cheaply. Li-ion batteries are several times more expensive than lead-acid batteries, but you can discharge them almost completely (80%), so you need less capacity. In addition, they also have a much longer service life (5000 cycles and more). As a result, they are gradually becoming cheaper than lead-acid batteries, especially if you look at the price per usable kWh. We expect this trend to continue. An additional advantage is their higher efficiency (more than 90%). A specific aspect of life-ion batteries is that they need a battery management system. After all, they can ignite spontaneously when used outside their operating range (thermal runaway), which is why a system is required to monitor this.

LIFE04PO batteries
If you charge by solar energy or a generator this provides 20-30% more usable energy. More importantly, if you charge via the generator, the battery is charged much faster. i.e. you save energy. The chemical composition of Lithium-iron-phosphate is extremely stable and eliminates a thermal meltdown as can occur with the cheaper Lithium-Ion batteries. So with the air-cooled LiFePO4 there is no risk of fire like with liquid-cooled li-on batteries, as they recently made the news annoyingly. The chemical composition of Lithium-iron-phosphate (LiFeP04) A LiFeP04 battery does not have the highest power density, but it is a safe composition that ensures that batteries can be built that are a good and reliable replacement for lead-acid batteries.
Two types are distinguished: the so-called cylindrical and prismatic cells. Javac prefers the prism cells, these cells offer all the advantages of the LiFePO4 composition and offer a great performance during charging and discharging. These have a rectangular plate construction with a positive and negative pole at the top or front. You now understand why a LiFE4PO battery is a very good replacement for a lead-acid battery. However, there are a number of conditions regarding the charging and discharging of Lithium-Ion batteries that must be carefully observed to avoid damage.
Usually, after a full charge, a lead-acid battery will be balanced enough to operate properly. With a Lithium-Ion battery, the lifespan is extended by applying a BMS (battery management system) that monitors each cell and transfers excess charge from one cell to the next. A Lithium-Ion battery is much more sensitive to this imbalance in the cells. Without rectifying this, the battery will quickly become unbalanced and lead to premature failure of one of the cells. All our Lithium-Ion batteries are equipped with this technology as standard. A Lithium-Ion battery provides a very constant voltage from fully full (charged) to almost empty (80% discharge). The voltage drop is then less than 2V in a 13.2V system. This is therefore a very stable DC voltage which only really goes down at the end.

Nickel iron batteries.
The nickel-iron battery is a very old technology. They have been somewhat forgotten due to their lower efficiency and high costs. An important advantage, however, is that these batteries are virtually indestructible. There are examples of batteries that Edison made himself and still work. Because of this, and because they do not contain any harmful materials, they have recently received attention from an ecological angle. Work is also underway to improve their drawbacks, which may make them an option for energy storage in buildings in the future.

WHAT POWER DOES THE JAVAC EDGE POWERBANK HAVE?

A relatively large battery capacity is required to bridge a prolonged power outage, but the capacity of the batteries is a determining factor in the cost price of the system. In systems where cost is important, a small battery capacity is therefore the mode. A small capacity of about two kilowatt hours is sufficient to increase self-consumption almost all year round, while the capacity of a larger battery would only be fully used a few times a year under the same conditions. An average household in Belgium consumes approximately 3,500 kWh on an annual basis. In the summer that is an average of 8 to 9 kWh per day. Assuming that on an annual basis all self-consumption is generated by solar panels. Then this is the ideal situation. So what can such a battery do for you? A simple answer to that is not difficult, every situation but also every day is different. In general you can say that the summer consumption can be generated directly or indirectly by means of a solar energy system. the solar panels and store it in a battery for consumption on the same day. You can therefore actually use that part of the generation of that day yourself without parking it on the grid. In principle, your battery should not be larger than that which is consumed that day, eg only 8 to 9 kWh. In practice, you also use electricity during the day and your storage needs will be smaller. Even if you are not present, the house simply consumes electricity. You can safely say that if you were on vacation and you let the fridge and freezer, etc. run, your consumption will be 2 to 4 kWh per day. This means that your battery must have a size of say 5 to 7 kWh to ensure that all the power you consume on those summer days is actually generated by the solar panels. The table below is based on an average household with an annual consumption of 3,600 kWh. All annual electricity is generated with solar panels based on a PV installation of 4,250 Wp (Watt peak) and with an average yield of 85% and therefore an annual yield of approximately 3,600 kWh. That with an average yield of an optimal placement to the south and an angle of inclination of 35º. On the roof.

The table shows that the battery does not need to have more than a certain maximum storage capacity. You want to send as little as possible to the power grid and therefore preferably use everything that you generate yourself. Now that consumption and generation are very large variables and that makes it difficult and you will unfortunately never get this optimally. Then the battery has to be very large and then it becomes quite expensive. The following two rules have been used as a logical basis for determining the optimal battery size; the maximum capacity does not have to be greater than what is consumed in a day. You consume the least in the summer. In this example 8 kWh per day. Being able to store more than your consumption is not useful, so the maximum capacity does not have to be greater than that consumption of 8 kWh. But on the day during generation, you also use part of that solar power. On balance, the optimum capacity is therefore lower than the maximum consumption.

What you do not generate in solar power is also not necessary to store. Of the solar power that is generated in the winter, you use a considerable part directly. This means that the optimal storage can be clearly below the daily generation of solar power. Then a small battery will suffice. We take some extra space in the table at the optimal capacity to ‘cover’ most variations and then round that up a bit, then we arrive at the last column in the table as the ‘optimum storage’. With the latter, we should bear in mind that during the day some electricity that you generate yourself is always used immediately, even if you are not at home. If we look at the result of all months, we can say that the battery must have a minimum capacity of 2 kWh. Then your own consumption will already go up considerably. A maximum of 9 kWh is required. But since you don’t use that extra large capacity that much, it doesn’t make sense. The ideal will be 6 to 7 kWh. But the final conclusion is as simple as it is logical. If the price is not the main argument and the intention is to use as much self-generated solar power as possible, the battery must be at least 9 kWh. And preferably even bigger because we will have to deal with fluctuations in generation and consumption. A day with a lot of generation and little consumption requires an extra large battery.
The larger you make the battery, the more of the power you ultimately use yourself, whether or not after the intervention of the storage in the battery. But the larger the battery, the more expensive your storage becomes, so you don’t opt for the maximum or the minimum, but usually for a happy medium. For this average household, a battery with a capacity of 5 to 6 kWh would probably be the most optimal. But we have to keep in mind that there is no such thing as an average family and even within that family there are outliers in terms of days when the consumption of electricity is very large or very small. On the other hand, there are also outliers in the day-to-day generation. Very sunny days alternate with very cloudy days. If you use very little on a day while your solar panels are having a super day (you are on the beach yourself and are not home until late), then you would have to store a lot and have a very large battery. The other way around – using a lot and generating little – is of course no problem. The above is a calculation exercise to see what the effect of a storage by means of a battery could be on its own use of its own generated power. You will also be less ‘disturbed’ during blackouts of the electricity grid.

Can the javac edge power bank handle long term storage?
Unlike some battery types that show a high self-discharge, the javac edge power bank distinguishes itself because it is technically perfectly suited to store energy for a long time. And with a low-load cycle of +2000 DOD at 100%, the investment has a particularly high return within the available service life. Batteries have a lifespan expressed in cycles, but regardless of consumption, they also have a maximum lifespan in years. A javac edge power bank of 11.4 kWh, for example, costs 7,000 euros. If you charge and discharge it daily to 20%, which does not happen in reality, you arrive at approximately 6000 cycles in 20 years (lifetime). The total
transported energy then amounts to 20 kWh x 6000 = 120 MWh. Calculate your profit

Frequently Asked Questions

Can the javac edge power bank catch fire?
No, the air-cooled LI-on battery used in the javac power edge bank does not pose a risk of fire, unlike other LI-on batteries, which are cooled by liquid
What else do I need besides the javac edge power bank to get started?
A CMS system to let your components communicate with each other

Will there be additional installation costs for my javac power edge bank?
For the first 100 systems in Belgium, there is a promotion where the installation costs are fully borne by the factory, with the exception of extra cables and extraordinary placements

If more power is generated than my consumption during a power cut, will it still be fed into the grid?
No, because the grid has been switched off, this power will be lost after the battery has been filled. Are there subsidies for a javac edge power bank?
This is not yet the case in our country, but it is in Germany, but different rates apply there, linked to a completely different power grid than ours, you may be eligible for a green loan at a reduced rate of 2%, ask for it at the recognized banks, including ING

Does the javac edge power bank have a standby consumption, like other batteries?
No, not at all
Do I need an extra inverter on my PV system to connect the batteries?
Possible with older installations, installations younger than 4 years usually not. Is your javac edge power bank a single-phase or 3-phase connection?

Both are possible, three-phase batteries are slightly more expensive than the mono-phase batteries. Tesla seems even cheaper than the javac edge power bank, how is this possible?
Tesla indeed offers a different product, first of all you have to feed their battery with a dc voltage from 350 to 450 Volts. In addition, they currently use Lithium Nickel Cobalt Aluminum Oxide cells (NCA), which can only handle 500 cycles. In addition, these cells must also be (water) cooled to prevent problems due to heat. Javac uses (LiFePo4), which do not require cooling and + 2000 cycles. For model 2, Tesla will switch to NMC cells, which can also handle a maximum of 1000 cycles – and not at full discharge. The advantage with them is the huge marketing machine, and everyone who just goes along with their story without investigating whether everything You will notice for yourself that Tesla hardly discloses any technical data precisely because of this weakness…

Why does a PV installation no longer work during a blackout?
A classic PV installation with solar panels coupled to an average inverter cannot function without a normally functioning electricity grid. After all, the inverter switches itself off as soon as there is an irregularity on the grid, for the sake of safety for people who restore the grid.