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.

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.


Victron Energy CANvu GX …information you can touch! It’s so convenient to be able access all your system information via touch screen – and because the Victron Energy GX is a sealed-unit, you can install it in some challenging environments!

P67 rating of the Victron Energy  CANvu GX means that it is completely protected against dust ingress, and can even withstand half an hour’s immersion in water 1 metre deep!

The Victron Energy CANvu GX is the latest addition to the Venus family – the information gateway which allows you to set-up, monitor and manage all the component parts of your private energy installation. In exactly the same way as you use the CCGXVenus GX; and Octo GX – the Victron Energy CANvu GX gathers data from your Inverter/ChargerBattery MonitorSolar Charge Controller, and batteries to allow optimal communication between components, maximising battery-charging and solar harvest.

And, of course, it allows you to interrogate the status of each device. But amongst the whole family, it is the Victron Energy CANvu GX which is ideal when the information is required to be displayed outdoors, or in difficult environments.

The arrival of the Victron Energy CANvu GX will be welcomed particularly by those users who work in the open. It is entirely at home on board vessels at sea, or on building sites – in applications such as the control panel of Hybrid Generators. It is also ideal in factories where industrial processes are wet, or dusty.


The unit comes with a dash/fascia mounting kit:


Please note that in order to operate the Victron Energy  CANvu GX you will need an IO Extender and wiring kit, and that this must be ordered separately:

The full colour screen of the Victron Energy  CANvu GX will be familiar both in appearance and size to anyone who has seen or used the CCGX. The system offers 3 VE.Direct ports and one USB port; a second, separate CAN-bus port; and it can receive digital inputs. It doesn’t have a buzzer. WiFi is not built-in, but a USB WiFi dongle can be attached. A comparison of features between all members of the GX family can be found here.

Justin Tyers


Lead acid battery charging in cold weather

This blog covers lead acid battery charging at low temperatures. A later blog will deal with lithium batteries.

Charging lead acid batteries in cold (and indeed hot) weather needs special consideration, primarily due to the fact a higher charge voltage is required at low temperatures and a lower voltage at high temperatures.

Charging therefore needs to be ‘temperature compensated’ to improve battery care and this is required when the temperature of the battery is expected to be less than 10°C / 50°F or more than 30°C / 85°F. The centre point for temperature compensation is 25°C / 77°F.

Cold weather also reduces a battery’s capacity. This is another factor that needs to be taken into consideration, along with the load and charge rate compared to the battery capacity (Ah). Both of these factors affect the correct and consequent sizing of a battery for your particular application.

Battery capacity in Ah is usually quoted as a 20 hour capacity rating at 25°C. The discharge rate or load can be written as 0.05C where for example C is the load factor of the 20 hour rated battery capacity at 25°C.

Worked examples: If a 100Ah 20hr rated battery then a 0.05 load would be 100 x 0.05 = 5 Amps or 100/20 which is also a 5 Amp discharge rate over that 20 hour period. A 10A load on a 100Ah 20 hour rated battery would therefore be a 0.1C discharge rate, a 0.2C discharge rate on a 200Ah would be 40A and so on. C ratings also relate to charge rates as well as discharge rates.

When buying a battery you may see its Ah quoted at 20 (the standard rate), 10 and 5 hour rates so you can see how load ‘shrinks’ the Ah. Some even quote at 25 hour rates, which often fools people into thinking they are getting a bigger battery than standard.

To recap – capacity reduces at low temperatures, as it does for higher discharge C rates above the 0.05C 20 hour rate. This reduction in capacity due to higher discharge rates is due to Peukert’s Law.

Graph showing the effect on battery capacity due to temperature and load:

Lead acid battery differences

Lead acid batteries come in a variety of types:
  • Wet lead with the ability to top up each of the six cells with de-mineralised water.
  • The so called ‘sealed’ wet lead leisure or rather maintenance free battery. These cannot be topped up and often have a green go or red no go cell inspection indicator.
  • AGM (Absorbent Glass Mat) valve-regulated lead-acid (VRLA), where the electrolyte is absorbed in a glass mat.
  • Similar to the AGM, but the electrolyte is held in a Gel.

All of the above are however lead based (as opposed to lithium) technology. Besides lithium batteries Victron Energy sell VRLA AGM and Gel monoblocs (6 x 2V cells in series) due to their superiority over wet lead monobloc types. Victron’s range consists of:

  • Gel (Better cycle life than AGM).
  • AGM (Better than Gel for higher loads and well suited for use with inverters).
  • AGM Telecom. Designed primarily for Telecom applications, but also excellent ‘footprint space savers’ for marine and vehicle applications.
  • AGM Super Cycle (Best if frequent discharge to 60-80% DOD is expected).
  • Lead Carbon Battery (Improved partial state-of-charge performance, more cycles, and higher efficiency).

Additionally Victron also sell specialist lead acid type batteries.

  • OPzV 2V individual battery cells. Long life, high capacity gel.
  • OPzS 2V individual battery cells. Long life high capacity flooded tubular plate batteries for specialist solar applications.

Temperature compensation and charging

Now we know about the kind of batteries, capacities and loads we are dealing with, we need to put some numbers together for temperature compensation and charging.

The recommended temperature compensation for Victron VRLA batteries is – 4 mV / Cell (-24 mV /°C for a 12V battery).

Besides accounting for cold weather charging the charge current should preferably not exceed 0.2C (20A for a 100Ah battery) as the temperature of the battery would tend to increase by more than 10°C if the charge current exceeded 0.2C. Therefore temperature compensation is also required if the charge current exceeds 0.2C.

How to achieve temperature and voltage compensated charging

There are a range of Victron products to achieve this.

With our range of inverter/chargers and since VE.Bus firmware version 415 was released some time back this has ensured that:

– Temp compensation continues down to -20C

– This is for all voltage set-points, except for float, storage and the start of bulk charging

– As soon as the temperature goes below -30C, the compensation mechanism is disabled (normal charge voltages are applied) and a warning is shown.

For systems that don’t use an inverter/charger – we can use Smart Battery Sense to ensure that charging sources provide optimal voltage and temperature compensated charging to your batteries, by wirelessly transmitting accurate battery voltage and temperature values to your Solar Charge Controller or Smart battery charger.

This information is then used to set the ideal charging parameters, resulting in more complete, faster charging – improving battery health and therefore extending battery life.

The Victron Toolkit app allows you to calculate cable sizes and voltage drop. Here’s an example where cable length is the round trip of the positive and negative battery charging cables. This is so you get an idea of what Smart Battery Sense automatically takes into account to ensure the correct charge voltage goes into the battery, by ensuring the charge voltage is compensated for and corrected due to any cable losses.

Victron’s range of SmartSolar MPPT Charge Controllers all work with the Smart Battery Sense. In fact I’ve just fitted one to my motorhome, along with the required Smart Battery Sense, due to the fact the leisure battery temperature location when compared to the location of the controller can have a difference of up to ten degrees. Definitely a case for ensuring accurate temperature compensation.

Other products can be connected too by using what we call ‘VE.Smart Networking support’. See the VE.Smart Networking page.

Conclusion

With the above solutions I know I’ll be happier now that my batteries are getting exactly the right charge due to optimal temperature and voltage compensation.

Why not make sure you are doing the same…

John Rushworth


When it comes to the buying decision for solar inverters, some buyers might be inclined to only look at pricing and spec sheets. While these are certainly buying criteria that should not be neglected, it is just a small portion of the bigger picture that needs to be looked at when choosing an inverter brand – because an inverter is more than what’s in the box.But why should you even consider Fronius Solar inverter?

As the solar inverter industry is becoming more commodified every year, inverter spec sheets are starting to look a lot more similar. Many inverter capabilities are driven by the same market requests and NEC code regulations, making features and pricing very similar across all inverter brands in the market. Therefore, a buyer could think that the only thing to look at is the price tag. However, it’s crucial to actually look past the spec sheet and the initial purchase price. When picking an inverter, you not only chose a piece of equipment, you are choosing a partner to work with for the next 20+ years. Thus, you might want to look into more than just “the box” and its price.

So what specific buying criteria is there beyond specs and price? The inverter is a critical component of a solar system, as it is not just responsible for DC to AC conversion, but also for the safety of a system, maximum power point tracking, grid interconnection and system monitoring. It is obvious that the inverter and its performance have a big impact on a system’s Levelized Cost of Energy (LCOE) and profitability – inverter uptime, operation & maintenance (O&M) programs and warranty matter in that regard, and this is where the company behind the inverter plays a crucial role.

54kw fronius solar power system installed in Accra

When choosing an inverter partner for the long term, it is crucial that this partner is around beyond the lifetime of a system. Therefore, financial stability and bankability, as well as a global footprint with a local support infrastructure are key aspects to look at. There is no doubt that the fairly fragmented inverter market will see further consolidation, given the ongoing price pressure. This increases the risk of certain manufacturers going out of business and leaving both installers and system owners in the lurch.

Furthermore, an easy to reach manufacturer support hotline and personal, long-lasting relationships on manufacturer’s level help installers through the entire process from designing systems to after-sales service for 20+ years – ensuring uptime and quick service. Since all power electronics can fail at some point, customer-friendly warranty terms and an easy RMA process are making a big difference. Power electronics manufacturers from advanced industries even offer spare part kits among certifications for contractors to conduct repairs cost-effectively in the field and within one truck-roll – a big impact on the profitability of a system.

All these aspects make a big difference and cannot be found on a spec sheet or on the price tag. Make a smart choice. Do not just look at the spec sheet and the price tag, when picking your  solar inverter. It’s a decision that will impact you over the next 20+ years and you want to be sure that your considerations are aimed at this period of time too.That is why Fronius solar inverters is a great choice.

NOCHESKI – YOUR INVERTER PARTNER FOR THE LONG TERM

Fronius has been in business for more than 70 years and shows a proven track record of long-lasting customer relationships and ongoing support for every product ever shipped. The company is privately held and cash operated, providing highest bankability. Fronius business is based on three independent business units which focus on completely different industrial sectors (Welding, Solar, Battery Charging) – yet they are based on a common technological focus on energy conversion. The Fronius 24/7 Service Solutions for inverters include online monitoring, Solar Online Support around the clock and the Fronius Solutions Provider program, a network of certified installers with direct access to Fronius.

To learn more about the Fronius Solar Solutions, contact [email protected] today or call 0244270092 to speak to our product specialist


The fronius range of inverters are very suitable for grid-tie solar power systems and are currently being deployed all over the country by Nocheski solar

Ghana:Organizations to shift to solar net metering system

Mr Kwabena Otu Danquah, the Head of Renewable Energy Promotion of the Energy Commission, has advised organisations to shift to the solar net metering system to save them from getting into the higher consumption rate bracket.

 

He said net metering was a mechanism that fed the national grid with surplus solar energy from households while assisting them to save cost and urged consumers to take advantage of it.

Mr Danquah was speaking at a two-day solar industry workshop in Accra organised by the Netherlands Development Organisation (SNV) and the Association of Ghana Solar Industries (AGSI) on current initiatives and opportunities in Ghana’s energy sector.

He said the Energy Commission, in collaboration with the Electricity Company of Ghana, had installed 35 net metering systems in various homes in Accra on a pilot basis.

“We are waiting for the Public Utilities Regulatory Commission (PURC) for the gazette to ensure that the new solar metering system fully takes off in Ghana,” he said.

Mr Danquah said the Energy Commission had created the enabling environment to ensure the attainment of enough renewable energy targets by 2020.

grid-tie solar power system with battery bank using victron and fronius systems

He said by the provision of the Renewable Energy Act 2011, 832, the Energy Commission, in collaboration with the Ghana Standards Authority, would enforce the law on the importation of renewable energy products that would meet good standards and certification.

He said: “The solar technology we know are perfect but the installation is the problem, hence the need for the Energy Commission to license all electricians and develop a training curriculum to train technicians to ensure good certification of solar.”

Mr Emmanuel Aziebor from the Netherland Development Organisation, a resource person, urged stakeholders in the solar industry to come out with substantive business models to convince the microfinance companies to invest in solar energy.

He advised the technical experts to support and sustain the technology whilst training more technicians on it.

Mr Aziebor said: “We need to have people prepared, trained and exposed to solar energy while looking at the local production of the products in future.”

Mr Eric Omane Acheampong, the President of AGSI, advised the members to develop activities on networking to enable them to assess their progress while sharing knowledge.

Mr James Robinson, the SNV Leader for Energy Sector, Ghana, gave the assurance that the SNV would continue to facilitate the activities of AGSI to sustain and promote solar energy in the country.

SOURCE:ENOCH DARFAH FRIMPONG/GRAPHIC ONLINE


Solar PV Power Paradigm Shift- The Ghana case.I am not that kind of a man, but I have been in the company of other men who in the midst of challenges rather saw them as opportunities to change the paradigm.

I strongly believe that very few energy planners and experts would disagree that Energy Independence for Ghana is an important, even urgent, goal.

But the question remains, is shifting the energy paradigm realistic; and if so, how?

And do our politicians and related institutions have the needed passion and spirit to embrace the new paradigm in our energy sector?

In recent years it has become so glaring that the conventional energy paradigm (fossil fuel tradition) has rapidly lost ground in comparison to the concept of Sustainable Development, as it is based on the intensive use of non-renewable fossil fuels — causing environmental degradation and posing Global Energy Security Risks.

Thus, a modification in our energy paradigm is necessary for our energy independence. A paradigm shift in the goals of energy policy should take place: toward independence, security of supply and climate change. Transition to a sustainable energy system is one of the critical challenges humankind faces in achieving energy independence in the new millennium.

Ghana is a country that has unbelievable solar energy potential; but, sadly, solar energy sources contribute only 0.1% (on-grid+ off-grid) of the total installed capacity for the total installed power capacity of 2104.5 MW in Ghana. (VRA: Facts & Figures).

Some people may say I am overly obsessed with the idea of solar energy for our small but incredibly energy-resource-rich nation.

It’s true – I am! But is it practical for Ghana to actually pursue this objective?

Talking of our potential, Wa — capital of the Upper West Region — has the highest level of solar irradiation (5.524 KWh/m2-day) across the country.

May is the month with the highest solar irradiation (5.897 KWh/m2-day), with August recording the lowest measurement (4.937kWh/m2-day) in Wa.

Akim Oda, conversely, is the location that records the lowest radiation (4.567kWh/m2-day) measurements across the country.

The highest measurement in Akim Oda was recorded in the month of April (5.176kWh/m2-day) and the lowest in August (3.802kWh/m2-day). See Table 1. 

As a nation we are blessed with daily sunshine that averages 5 hours, which ranges between about 7 hours and 4 hours for the northern and southern regions of the nation respectively. Ghana also has annual average daily solar radiation of about 4.5 to 5 KWm2/day. 

Table 1: Summary of Solar irradiation in kWh/m2-day – SWERA Report

Synoptic Station Ground

(kWh/m2-day)

Satellite

(kWh/m2-day)

% Error
Kumasi 4.633 5.155 -11.3
Accra 5.060 5.180 -2.3
Navrongo 5.505 5.765 -4.7
Abetifi 5.150 5.192 -0.8
Akuse 4.814 5.58 -15.9
Wa 5.520 5.729 -3.7
Akim Oda 4.567 5.177 -13.3
Wenchi 5.020 5.093 -1.5
Ho 5.122 5.223 -2.0
Kete Krachi 5.280 5.345 -1.3
Takoradi 5.011 5.200 -3.8
Yendi 5.370 5.632 -4.8
Bole 5.323 5.570 -4.6

 

Anti-islanding made easy: the anti-islanding box The anti-islanding box is a complete pre-wired and easy to install anti-islanding device consisting of a Ziehl anti-islanding relay (model UFR1001E or model SPI1021), the required circuit breakers and a 63A contactor. For specifications of the Ziehl relay

Anti-islanding made easy: the anti-islanding box
The anti-islanding box is a complete pre-wired and easy to install requured by law in certain countries for net meteringinstallations

Assuming we are to use only 23,854km² which is 10% of the total land area (238,585 km²) of Ghana to harness the sun’s energy with PV panels of 15% conversion efficiency, then Ghana would harvest 4,114 TerraWattHours of energy per year. 

This amount is equal to 2.42billion barrels of oil.

Consequently, if we juxtapose this amount with our current oil production in the Jubilee Field, then it is about 27 times the current crude oil production of Ghana per year.” See Chart A on Ghana PV Output.

In Ghana, Solar PV applications are gradually receiving acceptance in most places. However, despite improvements in local Research and Development (R&D) efforts, the body of knowledge on these technologies and their market potentials is considerably inadequate.

Launching major national initiatives on these technologies — such as the President’s 200,000 solar rooftops for households — requires a robust knowledge base and capacity.

In all, PV technologies are showing increasing promise in terms of efficiency improvements and cost. The estimated lifetime of PV modules are 25 years, and this makes them exceptionally attractive for investors.

The victron 500va phoenix offgrid inverter is excellent for small offgrid solar installations.its connectible to both Apple and Android smartphones, tablets, macbooks and other devices (VE.Direct Bluetooth Smart dongle needed)

The victron 500va phoenix offgrid inverter is excellent for small offgrid solar installations.its connectible to both Apple and Android smartphones, tablets, macbooks and other devices (VE.Direct Bluetooth Smart dongle needed)

Today, except for the Solar PV Panels produced in Kpone-Tema by Strategic Power Solutions (SPS) — a subsidiary of Strategic Security Systems International Limited, almost 80% the PV modules on the Ghanaian market are imported.

Solar PV systems can be extensively used for a wide range of electrical energy requirements: including solar home systems, water pumping, refrigeration and telecommunications that will reduce the load curve of electricity demand.

It has been estimated that solar rural electrification is about 30% cheaper than the cost of grid extension to rural communities that are about 18 to 20km from the nearest grid station.

However, there are still economic and institutional obstacles that limit this ability to self-generate power. For instance, while it is practical to install solar panels on a home, it is more difficult to scale-up these systems for commercial and industrial-sized projects. Scale is a critical issue in energy generation, as with scale comes lower project costs and greater efficiency.

For privately distributed generation projects, both small and large, to make greater contributions toward our national energy independence, there needs to be continued evolution of the bold policies that first introduced grid-connection rights and net metering in our renewable energy act.

The government must as a matter of urgency assist all consumers anywhere in the country to benefit from the net-metering incentive for solar power consumers. Again, due to the high upfront cost, government must establish a renewable energy revolving credit fund whereby solar consumers can borrow money to finance solar systems without making large up-front payments and without paying high interest rates to banks or private financiers.

Also, the PURC must establish a coherent pricing tariff for distributors to buy power from private solar-farm developers. This could unlock an untapped source of clean, reliable, economical power for Ghana.

While not easy to accomplish, these advances are achievable – and, importantly, they don’t need to cost the tax payers any money. However, they depend on the political will and leadership of our energy-sector authorities.

This an original story by Maxmillian Kwarteng and has been featured on BFT online


Apparently the economics for backup power alone just aren’t that attractive.

Tesla has quietly removed all references to its 10-kilowatt-hour residential battery from the Powerwall website, as well as the company’s press kit. The company’s smaller battery designed for daily cycling is all that remains.

The change was initially made without explanation, which prompted industry insiders to speculate. Today, a Tesla representative confirmed the 10-kilowatt-hour option has been discontinued.

“We have seen enormous interest in the Daily Powerwall worldwide,” according to an emailed statement to GTM. “The Daily Powerwall supports daily use applications like solar self-consumption plus backup power applications, and can offer backup simply by modifying the way it is installed in a home. Due to the interest, we have decided to focus entirely on building and deploying the 7-kilowatt-hour Daily Powerwall at this time.”

The 10-kilowatt-hour option was marketed as a backup power supply capable of 500 cycles, at a price to installers of $3,500. Tesla was angling to sell the battery to consumers that want peace of mind in the event the grid goes down, like during another Superstorm Sandy. The problem is that the economics for a lithium-ion backup battery just aren’t that attractive.

Even at Tesla’s low wholesale price, a 500-cycle battery just doesn’t pencil out against the alternatives, especially once the inverter and other system costs are included. State-of-the-art backup generators from companies like Generac and Cummins sell for $5,000 or less. These companies also offer financing, which removes any advantage Tesla might claim with that tactic, as GTM’s Jeff St. John pointed out last spring.

“Even some of the deep cycling lead acid batteries offer 1,000 cycles and cost less than half of the $3,500 price tag for Tesla Powerwall,” said Ravi Manghani, senior energy storage analyst at GTM Research. “For pure backup applications only providing 500 cycles, lead acid batteries or gensets are way more economical.”In Ghana  good  quality lead acid batteries such as the AGM telecom batteries retail at $219/Kw/hr and can be purchased at nocheski Solar (Victron Energy partner ) in the port city of  Tema. These AGM batteries have 1800 cycles at a D.O.D of 30% or 750 cycles at a D.O.D of 50%

 AGM telecom battery by victron energy

AGM telecom battery by victron energy

In California, batteries can benefit from the state’s Self-Generation Incentive Program (SGIP). But California regulators have indicated that battery systems need to be able to cycle five times a week in order to be eligible, which would exclude Tesla’s bigger battery.

“In current discussions on SGIP program overhaul, it is very likely that stronger performance requirements may get added, which will make a 10-kilowatt-hour/500 cycles product outright ineligible (if cycled only once a week), or last only 2 years (if cycled every weekday for about 500 cycles over 2 years),” said Manghani. “In short, the market’s expectation is that for a $3,500 price tag, the product needs to have more than just 500 cycles (i.e., only backup capabilities).”

Backup power alone simply doesn’t have as strong a case as using a battery for self-consumption. That said, the opportunities for self-consumption are still few and far between.

A GTM Research analysis for residential storage, purely for time-of-use shifting or self-consumption. found that the economics only pan out in certain conditions. In Hawaii, for instance, the economics of solar-plus-storage under the state’s new self supply tariff looks only slightly more attractive than solar alone under the grid supply option.

“So it comes down to the question of customer adoption of a relatively new technology for only slightly improved economics,” said Manghani. “This doesn’t mean residential customers are not deploying energy storage,” but he noted that these were the early adopters.

Tesla appears to be focusing its efforts on first movers and the markets where storage for energy arbitrage and self-consumption makes economic sense.

While the 10-kilowatt-hour option has been removed, the Powerwall website continues to offer specifications for Tesla’s 6.4-kilowatt-hour battery designed for daily cycling applications, such as load shifting. The battery is warrantied for 10 years, or roughly 5,000 cycles, with a 100 percent depth of discharge. The wholesale price to installers is $3,000.

The smaller battery is often marketed as 7 kilowatt-hours, which would appear to have a price of $429 per kilowatt-hour. In realty, it’s a 6.4 kilowatt-hour battery at a price of $469 per kilowatt-hour.

A bigger, cheaper or more integrated battery product could soon be added to Tesla’s lineup. In January, CEO Elon Musk announced a new Powerwall option will be released this summer.

“We’ve got the Tesla Powerwall and Powerpack, which we have a lot of trials underway right now around the world. We’ve seen very good results,” said Musk during a talk to Tesla car owners in Paris, The Verge reports. “We’ll be coming out with version two of the Powerwall probably around July, August this year, which will see [a] further step-change in capabilities.”

At this point, it’s unclear what the “step-change” will be.

 

 


Why your Lead Acid Battery is all Swollen Up? Working in the solar Energy industry in Ghana, I often come across several batteries that are swollen up .These mostly lead acid batteries have often than not, been purchased at very high prices not too long ago. On this particular occasion our team was conducting a survey at a prospects home in Tema when I noticed that all of her eight 100Ah batteries were swollen.

Typically a 100Ah battery will cost between $200-$300 depending on quality .In addition to this, most suppliers in Ghana give little or no warranty even though some global brands like Victron Energy give up to two year warranty on their batteries .This article aims to reveal to the public why lead acid batteries swell-up and how to avoid the problem.

Sealed lead acid batteries – both AGM and gelled electrolyte can swell up and expand sometimes. This happens due to the construction of lead acid batteries which is referred to as “recombinant”. They are constructed in such a way to allow absorption of gasses released during the chemical process inside the battery.

The positive and negative plates are placed very close together with only the thickness of the divider separating them. They are tightly secured in the cell cavity resulting in very little extra space inside the battery. When the cell plates expand, it exerts pressure on the inside walls of the battery. This situation can cause the battery case to swell resulting in possible splits and cracks at various points of the battery.

Why Do Battery Cell Plates Expand?

The cell plates most often expand due to overcharging of the battery. The battery may also expand due to shorting of the terminals of the battery. Both these situations results in heating up of the cell plates inside the battery. The lead of the cell plates has a high expansion rate when heated.

The outcome is that the battery experiences extreme pressure inside that swells up and deforms it. The swelling-up of the battery may also cause great damage to the internal components and parts.

Why your Lead Acid Battery is all Swollen Up ,How to Avoid Swelling Up of the Battery?

Overcharging or short-circuiting of the battery is the only reason for swelling up of the lead acid battery. The problem is not inherent in the battery itself. In order to avoid swelling up of the battery you need to tackle the underlying cause of the problem.

You need to follow proper instructions in charging the battery. The culprit may be that you are using a wrong charger when charging the battery. If the charger is providing too much current, this may be the cause for battery swelling up. For instance, if you used 24V charger to charge a 12V battery it will most probably result in overcharging of the battery.

Whatever the reason for overcharging of the device, the end result is the swelling up of the battery. To avoid the prospect of overcharging or short-circuiting of the battery, you need to take the following precautions:

  • Use the right type of charger that is fully compatible with the battery.
  • Ensure proper polarity when connecting the charger to the battery
  • Shield the battery terminals to avoid short-circuiting of the battery
  • Use a charger whose maximum charging capacity is lower than the battery
  • Using a good quality charger
Victron Energy Blue smart charger is a good choice for small battery banks in Ghana

Victron Energy Blue smart charger is a good choice for small battery banks in Ghana

 Battery charging tip: increase battery life with Victron 4-step adaptive charging

Victron developed the adaptive charge curve. The 4-step adaptive charge curve is the result of years of research and testing.

The Victron four-step adaptive charge curve solves the 3 main problems of the 3 step curve:

  • Battery Safe mode

In order to prevent excessive gassing, Victron has invented the ‘Battery Safe Mode’. The battery Safe Mode will limit the rate of voltage increase once the gassing voltage has been reached. Research has shown that this will reduce internal gassing to a safe level.Thereby  preventing swollen battery condition

  • Variable absorption time

Based on the duration of the bulk stage, the charger calculates how long the absorption time should be in order to fully charge the battery. If the bulk time is short, this means the battery was already charged and the resulting absorption time will also be short, whereas a longer bulk time will also result in a longer absorption time.

  • Storage mode

After completion of the absorption period the battery should be fully charged, and the voltage is lowered to the float or standby level. If no discharge occurs during the next 24 hours, the voltage is reduced even further and the battery goes into storage mode. The lower storage voltage reduces corrosion of the positive plates.

Once every week the charge voltage is increased to the absorption level for a short period to compensate for self discharge (Battery Refresh mode)

The above tips will help you to prevent your battery from getting swollen up and expanding. Taking precautions will not only protect your battery from being damaged but it will also minimize the threat of fire caused due to overheating of the battery.

Click here for more information on Victron Energy AGM & Gel batteries


What is Ghana’s solar power potential ? The country is blessed is with decent solar  irradiation year round.Ghana is in fact  notorious for its scorching sunlight.

Before I begin, permit me to ask this, if Oil and Gas for Thermal Power Plants and the other fossils are that “Cheap” as some want us to believe, why then are electricity rates still going up?Every hour, the sun radiates more energy onto our earth than the entire human population uses in one whole year. The technology required to harness the power of the sun is available now. Solar power alone could provide all of the energy Ghanaians consume and there is no shortage of solar energy like there has been with the Akosombo Dam in recent days. The truth is, we do not need advanced math skills to follow and perform the solar arithmetic to prove that Ghana’s energy independence could be achieved with solar energy.

Every square meter (1m²) of the earth’s surface, when exposed to direct sunlight, receives about 1000 watts (1 kilowatt) of energy from the sun’s light. In reality, this power per hour for every square meter (1m²) might be more or less, depending on the angle of sunlight, which changes with the time of day, and the geographical location. On average, the sub Saharan region of Africa receives about (3 – 4 kilowatt per hour) of solar energy.

Nonetheless, studies have revealed promising potential for this resource in Ghana. According to the SWERA Ghana Project report, Wa, the capital of the Upper West region, has the highest level of solar irradiation (5.524 KWh/m2-day) across the country. May is the month with the highest solar irradiation (5.897 KWh/m2-day), with August recording the lowest measurement (4.937kWh/m2-day) in Wa. Akim Oda on the contrary is the location that records the lowest radiation (4.567kWh/m2-day) measurements across the country. The highest measurement in Akim Oda was recorded in the month of April (5.176kWh/m2-day) and the lowest in August (3.802kWh/m2-day).

 

Table 1: Summary of Solar irradiation in kWh/m2-day – SWERA Report

Synoptic Station Ground

(kWh/m2-day)

Satellite

(kWh/m2-day)

% Error
Kumasi 4.633 5.155 -11.3
Accra 5.060 5.180 -2.3
Navrongo 5.505 5.765 -4.7
Abetifi 5.150 5.192 -0.8
Akuse 4.814 5.58 -15.9
Wa 5.520 5.729 -3.7
Akim Oda 4.567 5.177 -13.3
Wenchi 5.020 5.093 -1.5
Ho 5.122 5.223 -2.0
Kete Krachi 5.280 5.345 -1.3
Takoradi 5.011 5.200 -3.8
Yendi 5.370 5.632 -4.8
Bole 5.323 5.570 -4.6

 

This estimate tells that sunlight will provide useful solar energy for about 4 to 6 hours per day because during the early hours and late hours of the day the angle of the sun’s light is too low.Therefore, let us assume for every square meter (1m²) exposed to continuous direct sunlight [in an optimal geographical location] for an average of 4.5 hours a day, we will have received 4.5 hours x 1000 watts = 4500 watthours (4.5kwh/m²) of solar energy during the course of a day (Ghana’s solar power potential). It would be great if 100% of the sunshine became electricity, but solar energy and electricity are not the same. Technology accomplishes the conversion of solar energy to electricity.

What is Ghana's solar power potential?

Revelers enjoy sunlight and water at Ghana’s famous Labadi beach in Accra

Conversion of one form of energy to another always causes a loss of energy. In other words, the new form of energy will be less than the original. Efficiency is the word used to describe the difference in power resulting from the conversion of one form of energy to another. The efficiency of commercially available solar panels (PV) is now between 15% – 40.7%. This means that when a solar panel converts the sun’s light to electricity, only about 15 to 40.7 percent of the energy in the sunlight becomes electricity. The same thing is true of gasoline in your car and other thermal engines. Your car’s engine can only convert about 25 percent of the energy in gasoline to mechanical energy that turns the wheels.

With an average efficiency of 15 to 40.7 percent, every square meter (1m²) of solar photovoltaic cells (PV) would produce (4.5 kilowatthours of solar energy multiplied by 15% =) between 0.68 kilowatthours of electric energy per day.

Solar panels (PV) covering an area of 100m²(1 Plot of Land) would produce 100 x .68 = 68 kilowatthours of electricity per day. It is worth noting that 68kwh per day is a lot of electricity for a single family home.

 

Let’s juxtapose this arithmetic nationwide to the unused land surface:

– Size of Unreserved forest land in Ghana = 5 x 10³km² è 5 x 10⁹m².

– Assuming a Conversion Efficiency (Solar Panels) of 15%.

– Average Solar Irradiation 4.5kilowatthours (kwh) è 4500wh/day

– Annual average solar radiation = 4.5 x 365 è 1642.5kwh/m².y

– Assuming a Performance ratio, coefficient for losses of 0.75

So, 0.15 x 1642.5kwh/m².y x 5 x 10⁹m² x 0.75  è 923.9Gwh/y

What is Ghana's solar power potential ? The country is blessed is with decent solar  irradiation year round.Ghana is in fact  notorious for its scorching sunlight. power issues still prevailin May 2015 #DumorMustStop campaign was spearheaded by Ghanaian actress Yvonne Nelson and was patronized by many other celebrities

in May 2015 #DumorMustStop campaign was spearheaded by Ghanaian actress Yvonne Nelson and was patronized by many other celebrities

Like in Germany where Solar energy powered 50% of its midday electricity needs on May 26, 2012, this amount of energy can be used for same in Ghana.It is interesting to note that this amount of energy has been calculated from an area of 5,000km² which is only 2% of the total surface area of Ghana.In 2004, Ghanaians consumed 5,158 gigawatthours (GWh) of electricity. NEDCO alone contributed 340GWh out of this figure. This contribution from NEDCO is only one third of my estimate of the calculated solar potential. It is estimated that about half of this amount is consumed by domestic (or residential) consumers for household uses such as lighting, ironing, refrigeration, air conditioning, television, radio and the like.

In conclusion, let me say that the improved technology surrounding solar power is very significant. It has brought clean energy within practical use. Given the significant environmental benefits, there is a very strong case for government intervention to accelerate the switch to solar power. Considering Ghana’s solar power potential,  the reluctance to switch to solar power is delaying our national progress in living standards.

Source: Maxmillian Kwarteng | Gramax Energy Group – GEG | [email protected]


100 MW Ghana Solar Farm Gets Funding

Home Energy Africa, which specializes in the development and sales of renewable energy products for businesses, governments, and residential homes in Africa, has obtained a $705,000 grant from the US Trade and Development Agency (USTDA) for the development of a solar PV power generation project in Ghana.

Projected to begin construction in 2017, ESI Africa reports that this solar project will generate 100 MW of power, providing electricity to approximately 80,000 average homes in the country.

The agreement between the two countries was signed by Robert P. Jackson, the US Ambassador to Ghana, and Charles Sena Kwadzo Ayenu, CEO of Home Energy Africa.

“Lack of power is a challenge we see across sub-Saharan Africa. Two out of three people in this region lack access to electricity. That hinders business, and it hinders prosperity. We’ve made increasing access to power one of the top priorities for our bilateral relationship. Today’s grant is just one more way we’re bringing together government and the private sector to make Ghana’s future brighter,” said Jackson.

Boosting the Supply of Electricity

“One of Ghana’s paramount constraints to sustainable economic growth is the country’s inadequate electric power supply. This grant will support us in bringing our solar power PV project to financial close in order to fill the gap in power supply, meet Ghana’s goals for clean and sustainable energy, help create over 200 jobs to local communities and provide electricity to at least 80,000 average homes in Ghana,” said Mr. Ayenu.

Ayenu stated Ghana presently has 2,450 MW of installed capacity, adding: “The government of Ghana aspires to double that capacity to 5,000 MW this year, including 10% from renewable sources.”

The USTDA grant targets providing technical assistance to Home Energy Africa by using GreenMax Capital Advisors, an American firm, in finalizing the legal and financial details necessary to implement the project. Project assistance includes preparation for power purchase agreement negotiations with the Electricity Company of Ghana, services contracts, and financial arrangements.

Ayenu said the signing of the grant was the last barrier that the company has had to cross for work to begin on the project. He added that the firm has also acquired a 30% equity funding agreement for the $150 million project.

Originally published on Planetsave.