How to choose the best Solar battery in Ghana

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victron energy phoenix inverter compact in a box-bluepower+fronius lithium battery-agm vs lithium

Everybody wants the best solar battery in Ghana.There are certain specifications you should use when evaluating your solar battery options, such as how long the solar battery will last or how much power it can provide. Below, learn about all of the criteria that you should use to compare your home energy storage options, as well as the different types of solar batteries.

LITHIUM VS AGM Ghana

freedom won lithium-ion battery installed in Accra,Ghana

How to compare your solar storage options

As you consider your solar-plus-storage options, you’ll come across a lot of complicated product specifications. The most important ones to use during your evaluation are the battery’s capacity & power ratings, depth of discharge (DoD), round-trip efficiency, warranty, and manufacturer.

Capacity & power

Capacity is the total amount of electricity that a solar battery can store, measured in kilowatt-hours (kWh). Most home solar batteries are designed to be “stackable,” which means that you can include multiple batteries with your solar-plus-storage system to get extra capacity.

While capacity tells you how big your battery is, it doesn’t tell you how much electricity a battery can provide at a given moment. To get the full picture, you also need to consider the battery’s power rating. In the context of solar batteries, a power rating is the amount of electricity that a battery can deliver at one time. It is measured in kilowatts (kW).

A battery with a high capacity and a low power rating would deliver a low amount of electricity (enough to run a few crucial appliances) for a long time. A battery with low capacity and a high power rating could run your entire home, but only for a few hours.

Depth of discharge (DoD)

lithium vs AGM ,DEPTH OF DISCHARGE GRAPH,GhanaMost solar batteries need to retain some charge at all times due to their chemical composition. If you use 100 percent of a battery’s charge, its useful life will be significantly shortened.

The depth of discharge (DoD) of a battery refers to the amount of a battery’s capacity that has been used. Most manufacturers will specify a maximum DoD for optimal performance. For example, if a 10 kWh battery has a DoD of 90 percent, you shouldn’t use more than 9 kWh of the battery before recharging it. Generally speaking, a higher DoD means you will be able to utilize more of your battery’s capacity.This has always been an issue in Ghana .Most people have erroneous impression that batteries need to be completely drained for batter performance.

Round-trip efficiency

A battery’s round-trip efficiency represents the amount of energy that can be used as a percentage of the amount of energy that it took to store it. For example, if you feed five kWh of electricity into your battery and can only get four kWh of useful electricity back, the battery has 80 percent round-trip efficiency (4 kWh / 5 kWh = 80%). Generally speaking, a higher round-trip efficiency means you will get more economic value out of your battery.

Battery life & warranty

For most uses of home energy storage, your battery will “cycle” (charge and drain) daily. The battery’s ability to hold a charge will gradually decrease the more you use it. In this way, solar batteries are like the battery in your cell phone – you charge your phone each night to use it during the day, and as your phone gets older you’ll start to notice that the battery isn’t holding as much of a charge as it did when it was new.

Your solar battery will have a warranty that guarantees a certain number of cycles and/or years of useful life. Because battery performance naturally degrades over time, most manufacturers will also guarantee that the battery keeps a certain amount of its capacity over the course of the warranty. Therefore, the simple answer to the question “how long will my solar battery last?” is that it depends on the brand of battery you buy and and how much capacity it will lose over time.

For example, a battery might be warrantied for 5,000 cycles or 10 years at 70 percent of its original capacity. This means that at the end of the warranty, the battery will have lost no more than 30 percent of its original ability to store energy.

Manufacturer

Many different types of organizations are developing and manufacturing solar battery products, from automotive companies to tech startups. While a major automotive company entering the energy storage market likely has a longer history of product manufacturing, they may not offer the most revolutionary technology. By contrast, a tech startup might have a brand-new high-performing technology, but less of a track record to prove the battery’s long-term functionality.

Whether you choose a battery manufactured by a cutting-edge startup or a manufacturer with a long history depends on your priorities. Evaluating the warranties associated with each product can give you additional guidance as you make your decision.

LITHIUM VS AGM, Ghana

Victron Energy AGM super cycle batteries installation in Accra

Automotive companies are jumping on the energy storage bandwagon

Home energy storage technology and electric vehicles are a lot alike: they both use advanced batteries to create more efficient, sustainable products that can reduce greenhouse gas emissions.

As electric vehicles become more popular, more companies are dedicating significant research and development funds to developing batteries, and they’re expanding into the energy storage business. Tesla is the first mainstream example (with their Powerwall battery), but Mercedes-Benz and BMW are also bringing standalone batteries to the market in 2017.

How long do solar batteries last?

There are two ways to answer this question and the first is to determine how long a solar battery can power your home. In many cases, a fully charged battery can run your home overnight when your solar panels are not producing energy. To make a more exact calculation, you’ll need to know a few variables, including how much energy your household consumes in a given day, what the capacity and power rating is for your solar battery and whether or not you are connected to the electric grid.

For the sake of a simple example, we’ll determine the size of a battery needed to provide an adequate solar plus storage solution with national average data from our research at Nocheski Solar. The average Ghana household will use roughly 15 kilowatt-hours (kWh) of energy per day and a typical solar battery can deliver some 5 kWh of capacity. Thus a very simple answer would be, if you purchased three solar batteries, you could run your home for an entire day with nothing but battery support.

In reality, the answer is more complicated than that. You will also be generating power with your solar panel system during the day which will offer strong power for some 6-7 hours of the day during peak sunlight hours. On the other end, most batteries cannot run at maximum capacity and generally peak at a 90% DoD (as explained above). As a result, your 5 kWh battery likely has a useful capacity of 4.5 kWh.

Ultimately, if you are pairing your battery with a solar PV array, one or two batteries can provide sufficient power during nighttime when your panels are not producing. However, without a renewable energy solution, you may need 3 batteries or more to power your entire home for 24 hours. Additionally, if you are installing home energy storage in order to disconnect from the electric grid, you should install a few days’ worth of backup power to account for days where you might have cloudy weather.

 

Solar battery lifespan

The general range for a solar battery’s useful lifespan is between 5 and 15 years. If you install a solar battery today, you will likely need to replace it at least once to match the 25 to 30 year lifespan of your PV system. However, just as the lifespan of solar panels has increased significantly in the past decade, it is expected that solar batteries will follow suit as the market for energy storage solutions grows.

Proper maintenance can also have a significant effect on your solar battery’s lifespan. Solar batteries are significantly impacted by temperature, so protecting your battery from freezing or sweltering temperatures can increase its useful life. When a PV battery drops below -1.1 ° C, it will require more voltage to reach maximum charge; when that same battery rises above the 32.22 ° C threshold, it will become overheated and require a reduction in charge. To solve this problem, many leading battery manufacturers, like Tesla, provide temperature moderation as a feature. However, if the battery that you buy does not, you will need to consider other solutions like earth-sheltered enclosures. Quality maintenance efforts can definitely impact how long your solar battery will last. Temperatures in Ghana range between 25-35 deg Celsius.

https://www.youtube.com/watch?v=CIVBpSs2ma0

What are the best batteries for solar?

Batteries used in home energy storage typically are made with one of three chemical compositions: lead acid, lithium ion, and saltwater. In most cases, lithium ion batteries are the best option for a solar panel system, though other battery types can be more affordable. Order you Lithium batteries in Ghana here

  1. Lead acid

    Lead acid batteries are a tested technology that has been used in off-grid energy systems for decades. While they have a relatively short life and lower DoD than other battery types, they are also one of the least expensive options currently on the market in the home energy storage sector. For homeowners who want to go off the grid and need to install lots of energy storage, lead acid can be a good option.This is the most common solar battery type in Ghana.

  2. Lithium ion

    The majority of new home energy storage technologies, such as the , use some form of lithium ion chemical composition. Lithium ion batteries are lighter and more compact than lead acid batteries. They also have a higher DoD and longer lifespan when compared to lead acid batteries.  However, lithium ion batteries are more expensive than their lead acid counterparts.This is the least common solar battery type in Ghana

  3. Saltwater

    A newcomer in the home energy storage industry is the saltwater battery. Unlike other home energy storage options, saltwater batteries don’t contain heavy metals, relying instead on saltwater electrolytes. While batteries that use heavy metals, including lead acid and lithium ion batteries, need to be disposed of with special processes, a saltwater battery can be easily recycled. However, as a new technology, saltwater batteries are relatively untested, and the one company that makes solar batteries for home use (Aquion) filed for bankruptcy in 2017.This battery type is virtually non existent in Ghana.

EnGo – Smart Solar Street light pole

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EnGo – Smart Solar Street light pole is made by   EnGoPlanet ,the  sustainable solar lighting experts   recently launched a stylish new street light pole product which can even be retrofitted.The attachable design is of a solar cylinder module which can be quickly and easily mounted on any suitable pole for easy installation and disassembly.

Using 6 slim solar panels, with a solar cell efficiency of up to 21.2%, fixed to a hexagonal frame, ensures that half of them will face sun light at any time of the day.

The off-vertical cluster arrangement of the panels makes them less vulnerable to high-winds, less likely to accumulated dust and grime, and easier to clean.

The energy is harvested by a Victron SmartSolar MPPT 75-15. Bluetooth enabled, SmartSolar MPPTs include features which protect the battery from being too deeply drained, and have intelligent dynamic charge algorithms which work with the seasons to ensure the battery will at least periodically be returned to 100% charge.

EnGoPlanet use their own high-quality Lithium batteries, making the unit suitable for off-grid applications where night lighting is required. EnGo – Smart Solar Street light pole can also be used where a grid connection is present – in which case the units will run from their own batteries except where long-continued spells of poor weather require a power supplement to be drawn from the grid. This option is recommended for locations which are often cloudy, or shaded.

Alternatively, grid connected poles can be supplied without battery. Energy produced by the panels will be sent directly to the grid. Savings of up to 80% are possible.

EnGo – Smart Solar Street light pole  installations are also able to collect valuable environmental data which can be interrogated online. Other applications for the poles are for uses such as CCTV, sensors, wifi hotspots, and even phone charging points.

At Nocheski, we  look forward to installing  EnGo – Smart Solar Street light pole  soon

Justin Tyers

Lithium SuperPack batteries – an all in one solution

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Lithium SuperPack batteries – an all in one solution .These new Lithium-Ion, LiFePO4 chemistry batteries are often an ideal replacement for many 12V and 24V marine, automotive, caravan, motorhome, work vans and similar battery applications. It might even be for an overland motorcycle if using the smallest 20Ah version; to recharge a camera, phone or laptop for instance.

Other examples – take a typical small boat or van which may have a 110Ah to 220Ah lead-acid leisure battery for light continuous loads such as lighting, laptops, phones, instruments, powering a diesel heater, a fridge etc. And for shorter term loads maybe add a small inverter to charge power tools, run a small microwave or travel kettle for example. Using one SuperPack battery it matches well with the Phoenix Inverter VE.Direct 250VA – 1200VA range. Maybe you’ll add in around 100 to 200Wp of solar panels too using a small MPPT.

Regardless of the use, whichever SuperPack you choose it’ll be lighter than lead, can be smaller if you wish or give you more Wh in the same space – plus give you around 5 times the cycle life.

The main difference to Victron’s other lithium (often more kWh) offerings are the SuperPacks keep everything in one package, by having an integrated BMS and safety switch built-in. No additional components are needed as the internal switch will disconnect the battery in case of over discharge, over charge or high temperature. Simple, compact and safe.

If you are considering a new battery don’t immediately discount Lithium as being too costly. Whilst it is true that the capital cost of Li-ion is greater than that of quality AGM or Gel batteries – it is also true that the cost of ownership can be less than lead acid types. Much depends on your application, but rest assured – life with Li-ion is far less hassle than lead.

Over the last 8 years on my sailing yacht I’ve run AGM lead leisure batteries and Lithium-Ion propulsion batteries. Initially it was AGM for propulsion before discovering the effectiveness of Lithium. That journey taught me a lot about loads, capacity, cost and battery life – it’s one of the reasons why I think we’ve reached a tipping point and why these new SuperPack batteries may just be the ticket for your next project or battery replacement.

If in the first instance you are unfamiliar with AGM vs Lithium, then here’s a blog that explains that.

When to use a SuperPack?

Every battery size and type has it’s own particular use. For instance you may use the Lithium battery 12,8V & 25,6V Smart and the Lithium battery 24V (LiFePO4 & NMC chemistries) ranges (all of which have an external BMS) in quite different applications to the new SuperPack range. So, where to use the SuperPacks?

When it comes to replacing lead acid type batteries such as AGM and Gel in many applications, the SuperPack range can be considered the next generation after lead – making it far easier to replace lead with lithium. The only caveats being replacement is down to certain parameters being met, namely – Capacity (Ah), Voltages (12.8V & 25.6V), Discharge and Charge currents (C rates). Do in that case be sure that your chosen replacement fits your criteria by checking the datasheet and be aware the SuperPacks can be connected in parallel, but not in series. Hence in that case you would consider the other Victron lithium products named above.

The Lithium SuperPack

Victron Energy’s recently introduced Lithium SuperPack range comes in the following capacities and voltages:

12.8V & 25.6V Lithium SuperPack batteries:

  • 12.8V – 20Ah
  • 12.8V – 60Ah
  • 12.8V – 100Ah
  • 12.8V – 200Ah
  • 25.6V – 50Ah

These SuperPacks will give you 2,500 cycles to 80% depth of discharge at 25°C, much more than lead.

Comparison: SuperPack 60Ah LiFePO4 vs 90Ah AGM

Let’s compare the 60Ah Li-ion to say a typical 90Ah AGM battery discharged to the commonly accepted economic cycle life of 50% discharge for lead. That would give us 600 cycles at that DOD for the AGM compared to 2,500 at the even deeper discharge of 80% for the LiFePO4. Already you can see you may need to replace your lead-acid type battery 2 to 4 times as often as the Lithium. Of course loads, operating conditions and calendar life have to be factored in too. Regardless you get the idea – Lithium does more and lasts longer.

The benefits of Lithium don’t stop there though. Whilst LiFePO4 chemistry is considered the safest of them all, it’s worth considering other factors too to decide whether the reduced weight and volume of say NMC is of more importance for your application than LiFePO4 for example. Victron Energy do both types. These star graphs do a good job of explaining the differences: https://batteryuniversity.com/learn/article/types_of_lithium_ion

60Ah SuperPack

90Ah AGM

 
Weight
 9.5kg 27kg 
Size (mm)
 229 x 138 x 213 350 x 167 x 183 
Useable energy @ 25°C
 614Wh 540Wh 
Cycle life
 2,500 cycles 600 cycles 
Cost
 x 2.5 (approx)  x 1

Notes for the table above:

  • Useable energy and cycle life are based on 80% depth of discharge for Li-ion and 50% for AGM, these being considered the most economic use of those battery types.
  • Higher loads with lead will further reduce available Wh (Peukert’s Law) when compared to Li-ion.
  • Capacity is also reduced for both types by temperatures below their 25°C temperature rating (see their respective datasheets)

Make what you will of the above and whilst you are pondering the pros and cons don’t forget to take these additional factors into account for the comparison above.

  • Shipping: If you are replacing your lead from 2 to 4 times as often as Li-on and the fact that the lead weighs around 3 to 4 times as much (depends on Li-ion chemistry used) – then do consider the extra shipping costs.
  • Voltage stability: The voltage profile is far flatter for Li-ion compared to lead.
  • Voltage sag: Subject to the load, voltage sag with lead is significant compared to Li-ion.
  • Li-ion has much faster charge times and if charging from a generator it saves on generator runtime.

Other factors to consider

Is the above enough to convince you of why Lithium might be a better alternative than AGM or indeed Gel? Personally I’m sold on Lithium, but if you are not here’s a few things further to consider:

  1. A lead-acid battery will fail prematurely due to sulfation if it operates in deficit mode for long periods of time (i.e. if the battery is rarely, or never at all, fully charged). It will also fail early if left partially charged or worse, fully discharged.
  2. By comparison a Lithium-Ion battery does not need to be fully charged. This is a major advantage of Li-ion compared to lead-acid which needs to be fully charged often to prevent sulfation.
  1. Efficiency. In several applications (especially off-grid solar), energy efficiency can be of crucial importance. The round-trip energy efficiency (discharge from 100% to 0% and back to 100% charged) of the average lead-acid battery is 80%.
  2. The round-trip energy efficiency of a Li-ion battery is 92%.
  1. The charge process of lead-acid batteries becomes particularly inefficient when the 80% state of charge has been reached, resulting in efficiencies of 50% or even less in solar systems where several days of reserve energy are required (battery operating in 70% to 100% charged state).
  2. In contrast, a Li-ion battery will still achieve 90% efficiency even under shallow discharge conditions.

Make the switch?

Are you ready to make the switch from Lead to LiFe? If you’ve considered all the above I suspect you might be. And if you need more useable Ah why not run the sums on say a 100Ah Lithium SuperPack vs 220Ah AGM using the process I have above. Or indeed a 200Ah Li-ion SuperPack vs your choice of lead.Lithium SuperPack batteries – an all in one solution

Don’t forget too that Lithium has little or no Peukert effect when compared to Lead types. This is especially important when considering loads with lead-acid higher than 0.05C (Battery Ah divided by 20 or Ah multiplied by 0.05). In other words for a 100Ah AGM with a Peukert of say 1.15 or more and discharging at 0.25C (25 Amps in this case – which is 5 times the 20 hour rate) there will be significant reduction in capacity – as there will be at colder temperatures too. Li-ion has a Peukert of around 1.05 when compared to lead of around 1.15 to 1.25.

So – if you were discharging that 100Ah lead at 5 Amps (the 20 hour discharge rate at a temperature of 25 degrees centigrade) then the full capacity of 100Ah is still availaable and it’s not shrunk due to Peukert. But now if it were 0.25C, it’ll be around 80% of that original 100Ah capacity – or less, subject to load type and duration.Lithium SuperPack batteries – an all in one solution

The bottom line is you no longer have the Ah you purchased, whereas with Lithium there is little to no effect, helped by a lower Peukert and good voltage stability. That is especially important with constant inverter loads – a place where lithium shines. If you want to learn more about Peukert and run a spreadsheet to see such effects, then I have found this link most helpful.

Finally and one I’m always grateful of is vastly reduced charge times, no more waiting for hours of lead absorption charging to get from 80% to 100% SOC. Conversely Li-ion flies up to around 98% SOC in bulk with those last few percent in absorption to fully balance the cells – and unlike lead you don’t always have to fully charge to 100% as often. Note that your 12V charging system needs to accommodate 14.2V – 14.4V ‘absorption’ and ‘13.5V’ float. If charging from an alternator also note the maximum continuous charge currents for the 12.8V range, by checking the datasheet.

Downsides

Not wanting to sound too evangelical, we also need to consider the few downsides of Li-ion.

  • Higher upfront cost and to some extent higher capital risk.
  • Charging is restricted to the +5°C to +45° range, subject to an internal means of blocking the charge source when the temperature is below +5°C. Note this is currently automatically possible with Victron MPPTs when used in conjunction with the Smart Battery Sense for instance. Other products are being worked on to achieve this too and documentation to that effect will be updated in due course.
  • The SuperPack (unlike other Victron Lithiums) is not designed for series connections.
  • The peak and maximum continuous discharge current of the SuperPack range is not as much as some of our Lithium batteries as its related to the BMS and the disconnect being internal to the battery – so do check the datasheet to make sure the current peak and discharge ratings suit your needs – or choose from the Lithium battery 12.8V & 25.6V Smart or the Lithium battery 24V range or build a parallel SuperPack bank.Lithium SuperPack batteries – an all in one solution

Conclusion

Whatever your decision when purchasing new batteries, maybe it is time to give the Lithium SuperPack batteries a chance. There’s LiFe after Lead you know – but as I’ve shown that all depends on what you want to achieve. Is it less weight, less volume, maybe it’s capacity or voltage or any of the multitude of factors that go into choosing a battery system.Lithium SuperPack batteries – an all in one solution

Whatever you choose Victron have plenty of choice – with a large range of battery types and sizes: https://www.victronenergy.com/batteries

John Rushworth

Rhino Poaching Surveillance in the Kruger National Park

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The Kruger National Park is home to a third of the world’s remaining Rhino – a fact which makes the park attractive to poachers who kill Rhino just for their horns.Rhino Poaching Surveillance in the Kruger National Park

In order to try to prevent the Rhino from becoming extinct – Park Rangers have to be constantly on the lookout for poachers in a wilderness which extends to 2 million hectares. That’s an area equivalent to a box whose sides measure 140km/90miles – you can’t be everywhere at once, so the Rangers have installed some discreet technology to help.

Saving the Rhino is a race against time because the growth in poaching has been alarming: In 2007, 13 Rhino were poached in South Africa …by 2014 that figure had increased 9000% –  1215 animals were illegally slaughtered in that year alone.

Powdered Rhino horn has become more valuable than cocaine – fuelled by the misguided belief, particularly in the East, that it has medicinal value. When prices rose recently, Rhino became a target-interest of international organised crime – turning what was then localised illegal activity into something of global industry.

In order to maximise their policing, Kruger National Park Rangers have set up a number of radar detection systems, strategically installed to offer wide area surveillance, both day and night. Three or four units allow them to cover half the park area. The radar detects movement and plots it on a map. Remotely operated camera’s allow the operators to distinguish between  ‘Animal’ and ‘Human’ movement. Suspicious activity is then intercepted by truck or helicopter.

Financed mainly by charitable donations the surveillance installations are highly mobile, frequently moved, and can be packed for deployment by truck – or even slung under a helicopter and flown-in to new surveillance sites.

These mobile installations need reliable off-grid power source – for which Lithium battery specialist BlueNova located in Cape Town led the system design. Lithium Batteries are an ideal solution to frequently-relocated installations – amp for amp they’re almost 80% smaller and lighter than their Lead/Acid equivalents. And amongst a topography of scrub and boulder, PV panels offer discreet power-generation. They do not impinge on the visual amenity which is so important to wildlife tourists on safari; and they remain undetected by would-be poachers.

The power plant features 26V-8kWh BlueNova Lithium Ferro Phosphate battery (LiFePO4)

24V 3kVA Victron Multiplus

2 x BlueSolar Victron MPPTs  Solar Chargers to regulate the six-panel PV array.

 

Currently, three Rhino’s are killed illegally every day. At that rate the animals will soon face extinction. All that can be done to slow the decline should be done. Against armed poachers, the Kruger National Park Rangers are carrying-out a dangerous job with utter commitment to conservation – this technology helps them reduce the slaughter.