Nocheski solar

Dumsor:The politrix of Energy Efficiency VS Conservation

November 21, 2016

Erratic power supply AKA Dumsor has always been hot topic these past few years .Pronounced “doom-sore” (or more appropriately dum sɔ, “off and on”) is a popular Ghanaian term used to describe persistent, irregular and unpredictable electric power outages. Everybody from businesses to households has been affected one way or the other. In addition to this most Ghana residents have had to spend 200-300% more than what they used to spend on electricity five years ago.

2016 is an election year in Ghana and I hear lot of promises from political parties and politicians alike. These promises include, good roads, education, health, jobs and of course Energy .

Thousands of Ghanaians attended the much anticipated ‘Dumsor must stop vigil’ in Accra on Saturday.

The protestors clad in red and black outfits marched from the Total Filling station opposite the University of Ghana to the Tetteh Quarshie Interchange here in the Greater Accra Region.

The vigil was led by Yvonne Nelson and other celebrities such as Efya, DKB, Sydney,Van Vicker and a host of others. Watch the the video here

Can we be brutally honest with each other as Ghana residents?

Our energy demands have risen over the years and we require more capacity
Energy prices have risen all over the world and reliance on only hydro isn’t sufficient for Ghana anymore
There is no political party that can reduce electricity tariffs to rates that were being paid 5-10 years ago. Even if anybody tried, it wouldn’t be sustainable
Electricity prices will continue to rise in the coming years and the time to change our mindset is now
Ghana needs a serious national policy plan /implementation on energy matters
All the are above play a key role in Dumsor

I have to admit times are pretty hard in Ghana these days. A lot of people are unable to pay their utility bills. Some have actually resorted to either connecting utilities illegally or using less. Many people in Ghana have been caught, some of them being foreign businesses and all .I also know a few people who switch off their refrigerators or deep freezers at night.

Another interesting fact is that for those who are buying new electrical appliances, price becomes the most important or deciding factor so much such that efficiency is thrown out of the window.

While interacting with people we get these statements quite frequently: So you tell people to use less electricity and conserve it?” or “Your website has ideas on how to buy appliances, how does that relate to saving electricity?” The easiest way to save energy (or electricity) is to use less of it, but we have to be realistic in our approach. Our lifestyles are changing, and with increased pace of development, our need for appliances is increasing and so is our need for energy. Thus the ideal mix to save energy will involve both conservation and efficiency. Now let us look at what is the difference between the two.

Dumsor:The politrix of Energy Efficiency VS Conservation

kicking dumsor out of Ghana

What is Energy Conservation?

Whenever you use less of something that means that you are trying to conserve it. So if you use a 1100cc vehicle instead of a V8 vehicle, it means that you are trying to conserve fuel (among many other reasons why you would prefer to use 1100CC over a V8 motor vehicle). If you switch off lights when they are not needed, then you are conserving energy. When you increase the temperature at which you operate your air conditioner from say, 24 degrees to 25 degrees, you are conserving energy. You also conserve energy when you switch off your DSTV decoder boxes and TVs when they are not in use.

Energy Conservation is all about using energy only when it is required and using it as much as needed for the job and not wasting any amount of it. It requires a conscious effort from the user of energy to make sure that there is no wastage on a regular basis. It requires a lot of behavioral change and needs effort. It may not need any investment always.

So what is Energy Efficiency?

Energy efficiency in contrast means using lesser energy to do the same job. When you buy a car that gives more mileage, you use less fuel to travel the same distance. When you buy a 5 star rated air conditioner instead of a 3 or 2 star rated air conditioner, it means that for the same usage and in same conditions, you use less electricity (for the same temperature at which you operate them). If you use a 5 star rated air conditioner at higher temperature, you double the effect and combine energy efficiency with energy conservation.

Energy efficiency has more impact on your personal finances. An efficient appliance may cost more than an inefficient appliance. Although the additional capital cost may get recovered in form of electricity savings. Energy efficiency may not require physical effort but requires change in people’s buying patterns. It requires knowledge of various products and their efficiencies. If people start buying more of efficient products, manufacturers will start producing more of them.

Conclusion

Both energy efficiency and energy conservation have the same goal.That is to save energy and the same impact: saves money. Both can individually save energy but when coupled together can save double the amount of energy and money. It depends on your choices as to which one you like to do. A good mix of the two can ensure high savings with low investments and efforts. Finally ,going solar is a brilliant way to achieve all this in a single move by trying out our mini off-grid solar packages All these efforts will go a long way in curbing Dumsor

Is Tesla Discontinuing Its 10 Kilowatt Powerwall ?

October 8, 2016

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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

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

September 30, 2016

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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

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

Inverter Air Conditioners & Ghana’s Rising Electricity Tariffs

September 30, 2016

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Inverter Air conditioners & the rising electricity tariffs in Ghana

My Nigerian friends often say Ghanaian folk have a signature look, very dark skin and red eyes. This they claim is as a result of the scorching sun in Ghana. Ghana is hot o…….

Average temperatures often range between 35-40 degree Celsius with high levels of humidity . Due to the nature of the weather in Ghana Air-conditioning is no longer a luxury.Most homes and offices who can afford , have invested in one form of cooling or the other while those who cant have settled for fans.But what happens when there is erratic power supply and load shedding AKA Dumsor in Ghana? I bet that is another topic for another day.

little children cooling off in bowls of water at home on a sunny day in Accra,Ghana

Recent electricity price hikes in Ghana have made Air Conditioners a pain point for most who are concerned about their electricity bills. Electricity bills increase significantly when an air conditioner is added to the list of appliances in a household. Although it is difficult to significantly reduce the “big” impact of an air conditioner on your electricity bills, it can be managed by choosing the right technology. Also by following the right installation/maintenance/operation procedure and also putting into consideration the insulation of room where the air conditioner is being operated.

The latest and the most efficient technology that is available on market today is the Inverter Technology for air conditioners. Inverter technology is designed in such a way as to save 30-50% of electricity (units consumed) compared to regular air conditioning systems.At Nocheski ,we live up to our promise of driving your business with technology and we recommend the use of energy efficient appliances such as inverter Air-conditioners from brands including LG,Daikin,Carrier Samsung , Gencool, Hisense just to name a few.

How do air conditioners work?

For most people, air conditioner just throws cool air at the temperature one sets it at. But does it really work that way? In principle, an air-conditioner during the cooling process, takes the indoor air, cools it by passing it through evaporator and releases it back in the room. It is quite opposite to how our good old air coolers used to work. Air coolers used to take outside air, cool it with water and throw it in. But air conditioners just work on internal air. Along with evaporator an air conditioner also has a compressor that compresses the gas (refrigerant) in the AC to cool it that in turn cools the incoming internal air from the room.

In a regular air conditioner:

The compressor is either off or on. When it is on, it works at full capacity and consumes the maximum electricity it is designed to consume. If the thermostat reaches the temperature level set in the AC, the compressor stops and the fan (in AC) continues to operate. Then the thermostat senses that the temperature has increased, the compressor starts again.

https://www.youtube.com/watch?v=DvvPDm7I6W0

Air Conditioners with Inverter Technology

The inverter technology works like an accelerator in a car. When compressor needs more power, it gives it more power. When it needs less power, it gives less power. With this technology, the compressor is always on, but draws less power or more power depending on the temperature of the incoming air and the level set in the thermostat. The speed and power of the compressor is adjusted appropriately. Originally developed in Japan for use in air-conditioning systems, digital inverter technology is now applied globally in appliances such as refrigerators, washing machines and even microwave ovens.

digital inverter air conditioners,fridges, are getting popular in Ghana

Samsung has a new line-up of household appliances for the digital home that saves on cost and offers more features.

What is benefit of Inverter Technology?

Air conditioner is designed for a maximum peak load. So a 1.5hp AC is designed for a certain size of room and 1 hp for a different size. But not all rooms are same . A regular air conditioner of 1.5hp capacity will always run at peak power requirement when the compressor is running. An air conditioner with inverter technology will run continuously but will draw only that much power that is required to keep the temperature stable at desired levels. Hence Automatic adjustment of capacity based on the requirement of the room it is cooling and so requiring less electricity for efficient operation although air conditioner with Inverter Technology adjusts its capacity based on the room requirement, it is very important to install a right sized air conditioner in a room.

Its important that you evaluate the room and air conditioner capacity before you make a purchase.Moreover digital inverter technology appliances such at home further increases the business case for installing solar for home.This as a result of highly reduce electrical load. Check out our off-grid solar offers for 2-5 bedroom homes .For further clarifications on this subject ,you may contact our product specialist in Tema here

What is Ghana’s solar power potential……….?

September 30, 2016

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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.

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 | mkwarteng21@gmail.com

Victron Energy Multiplus inverter -improved faster switching

December 26, 2014

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Victron Energy Multiplus inverter -Now improved with faster switching to grid.It can now switch much faster from inverter mode to mains mode. Combined with our high peak power ratings, this makes it possible to switch to mains mode before shutting down in an inverter overload alarm. This is especially useful in Self-consumption Hub-1 and 2 installations: it allows using an inverter/charger with a nameplate power below the system power. Victron Energy Multiplus inverter improved: faster switching to grid

The old hardware will take approximately 8.5 seconds to switch from inverter- to charger-mode, the new hardware can do it within half a second. Some notes:

single phase installations will be even faster than the half a second mentioned;
fast switching is only possible in the 3xx firmware versions. The difference between 3xx on one hand, and 1xx and 2xx on the other hand is approximately another 0.5 second in the worst case scenario: slightly differing frequency, and inverter being 180 degrees out of sync with the grid;
all larger models, 3kVA and upwards, already have fast-switching since a long time;
do not forget the other limit to using an ‘undersized’ Victron Energy multiplus Compact in an installation: the AC transfer capacity. Max system load may never exceed the transfer switch capacity;
the load-shedding functions in the self-consumption hub-1 and 2 Assistants give options to further undersize a Victron Energy Multiplus Compact: use an external relay which is controlled via the Auxiliary output;
mentioned switching delays have not been measured exactly;
for parallel and three-phase operation, please check the Disqus comments below.

Lots of little details, but all together the conclusion is that this significantly reduces the chance of a Victron switching off in overload condition. Victron Energy inverter improved: faster switching to grid

Availability

Despite stock and production logistics, all different models are shipping with the new hardware. Below table gives an overview of the current situation, from our main warehouse DSV in the Netherlands.