portable FB

Combating both COVID-19 & Eskom Load-shedding through Portable Back-up Power Units

In between the team’s busy projects schedule in January 2021, the Zero Point Energy engineering team made some time for R&D to combat the dual crisis of COVID-19 and Eskom load-shedding, and the disastrous impact both have on home-based patients dependent on oxygen concentrator devices that need to run 24-7.

ZPE portable power supply

The ZPE portable power supply under demonstration

Helping to Save COVID-19 Lives through our Backup Power Experience

In trying to address the multiple concerns with current backup-up power solutions in the market that were raised by home-based medical practitioners & community care-givers, the team spent time refining a design to come up with a solution that was both practical and innovative.

All that is needed is to plug the unit into a normal wall plug, then plug the medical device into the socket outlet on the front door of the unit, and flick the switch for uninterrupted power even during load shedding!

Product Features & Advantages:

The resulting outcome of tinkering on our workbench was the portable backup power supply shown below. Some of its nifty features include:

1. Sufficient battery storage & inverter capacity for a 5L home oxygen concentrator to work at full capacity for up to 5 hours of load shedding, and factoring in any start-up surges and switching

2. Total system weight of under 25kg making it easily portable and transportable (compared to existing battery trolleys in the market weighing 63kg for equivalent power & storage capacity!)

3. No noise, no fuel emissions and no cumbersome start-up, storage and safety concerns as associated with diesel, petrol and gas generators

4. Designed & assembled to be easily maneuvered in & out of cars, and even up & down stairs using a small hand-truck

5. Use of modern lithium-ion battery technology and a high-spec’d battery charger, providing up to 5x longer lifespan (up to 10 years) and 2x faster charging to get from 5% back up to 100% charge (2 hours), compared to lead-acid batteries that would require 4 hours which is a concern if load shedding happens multiple times in a day

6. Integrated the system with a Raspberry Pi processor and customised software so that the system can be remotely monitored and configured via the Victron online portal to provide warning notifications to care-givers on a mobile device e.g. when battery level reaches a minimum threshold or when load shedding starts or stops

ZPE portable power supplyRemote monitoring screen accessible via mobile app or desktop

7. Use of top tier equipment & components such as Victron inverter/charger, Blue Nova lithium-ion battery, Hager electrical protection components and designed & installed in a manner that is safe, electrically compliant and plug & play for anyone to useZPE portable power supply

Top tier components went into assembly of the unit

8. Other functional benefits are the ability to charge cellphone/tablet devices from the system at the same time as medical devices are in use. The enclosure is also lockable and sturdy enough to be used as a temporary side table. There’s no noise nor emissions that would need to be a concern, so the unit can be located directly in the same room as patients requiring the medical device

Planned Roll-out

We intend to roll-out a few of these units to care-givers in first quarter of 2021 who constantly need to transport oxygen concentrators between different COVID-19 patient locations.

They now have a reliable, convenient and easy to transport back-up power supply that can give them peace of mind that their critical patients will always have constant power for their life-saving medical devices even during Eskom load shedding.

Contact Us

Feel free to contact us to see to learn more or request quotes:

Whatsapp: +27605218388 | info@zpenergy.co.za | @zeropointSA | www.zpenergy.co.za

Established in 2015, Zero Point Energy (Pt) Ltd is a proudly South African 100% black-owned & 41% female-owned sustainable energy company providing bespoke design, consulting engineering, turn-key Engineering, Procurement & Construction (EPC) solutions as well as Operational & Maintenance (O&M) services in the areas of renewable energy, energy efficiency, energy storage, off-grid and backup power in the Southern African commercial, industrial, residential, agricultural and public sectors.

Learn more about the company’s team here

hot water

A Comparison of PV, Solar Thermal, Gas and Heat Pump for Domestic Water Heating

A Comparison of PV, Solar Thermal, Gas and Heat Pump for Domestic Water Heating

Many domestic consumers are turning to renewable energy technology for their water heating needs. Several factors are behind this transition, including the cost of electricity, the instability of the national grid and the growing awareness about the need for sustainable living. The national building regulations also require that at least 50% of water heating be done with something other than an electrical element.

As with many products on the market, however, you can find widely contradicting claims with regards to the different technologies. In this article, we shed some light on the main water-heating technologies and the savings you can achieve with each of them.

Instantaneous Gas Water Heaters

gas water heater

Source: Service Champions

This option uses LPG to heat water instantaneously. There is therefore no geyser or hot water storage tank needed. 1kg of LPG “contains” 13.6kWh of energy and therefore can produce 11.5kWh of thermal energy if the gas heater has an average efficiency of 85%.

Solar PV Water-Heating Element

This option uses solar electric panels (PV panels) to power an electrical heating element. An electrical element is close to 100% efficient, meaning a 1kW element will consume 1kW of electricity to produce 1kW of thermal output. This power comes from a PV panel.

solar PV water heater

Source: Thermo Dynamics Ltd.

PV panels must be installed facing north and at a horizontal angle equal to the latitude of the location and it is critical that there is no shading on the panel. Shading as little as 2% of the panel surface can result in more than 50% panel output reduction.

The efficiency of the PV panels is around 17% (under lab conditions with the cell at 25°C). In real life, with the sun shining on the cell, it will heat up and cause a decrease in output power of about 8% (0.4%/°C with 20°C nominal operating cell temperature (NOCT)).

Panel ageing will typically result in a maximum degradation of 2.5% in the first year and up to 10% in 10 years. Next, you need a maximum power point tracking (MPPT) to ensure optimal power transfer from the panels to the element. A very good MPPT is typically around 95% efficient and therefore you lose another 5% of the available power.

 Solar Thermal Water Heaters

These water heaters use the radiation from the sun to generate heat. The size of the solar panel will determine how much energy can be collected from the sun. For example, if we have a 2.4m2 solar panel connected to a geyser, this might give us 60°C water at the end of a warm sunny day but, during cooler days with less sunshine, it might only be able to heat the water to 35°C. The solar controller will then use Eskom to heat the water to 60°C. If we have a solar panel that is only half the size (1.2m2), we would only get out half the energy and an electrical element will need to do the rest.

flatplate solar geyser

Source: UCUSA

A good quality flat plate solar thermal collector has an efficiency of around 73%. The output of a solar thermal collector de-rate based on the temperature difference between the water in the collector and the ambient temperature. Working on an average temperature delta of 17.5°C (heating water from 15°C to 60°C @20°C ambient) will give about a 10% reduction in output. Piping thermal losses on the insulated pipes connecting the solar panel to the geyser is about 10W/m.

Domestic Hot Water Heat Pump

These use a small amount of electricity to extract a lot of energy from the surrounding air. A heat pump also uses the sun’s energy but only indirectly, so it can work day and night, winter and summer. The efficiency of a heat pump is called coefficient of performance (COP). A COP value of 4 means that the heat pump produces four times as much thermal energy as what it uses electrically i.e. a 75% saving on the water heating bill.

ITS heatpumps

Source: ITS Heatpumps

Unfortunately, the COP of a heat pump is dependent on the ambient temperature and the water temperature and so, in a practical domestic hot water system using a well-designed heat pump, a realistic annual COP value is 3 i.e. a 66% saving on the water heating bill.

A Practical Example

A family of 4 that uses water moderately goes through about 200L of hot water per day. To heat 200L of water from 15°C to 60°C requires 10.4kWh. The standing loss of a B-rated 200L tank is 1.6kWh/day in the lab, but with installation piping included, it is typically around 3.6kWh/day. Therefore, the total energy requirement for this family’s hot water is 14kWh/day. If they are paying R2/kWh for electricity, their water heating costs them R840/month. Assuming that water heating typically makes up 50% of the total electrical bill, we are looking here at a family that spends about R1680 per month on electricity.

 

Let’s now look at what the different water heating technologies can do for them:

An instantaneous gas water heater would save them the standing losses on the geyser. They will therefore only need 10.4kWh of thermal energy per day. With a 85% average efficiency unit they will burn 0.9kg of gas per day. At R23/kg the monthly cost will be R624. Assuming a 10% annual electrical tariff increase as well as a 10% annual LPG price increase they will save R16278 over the next 5 years on their water heating bill.

Gas water heating will save R16278 over the next 5 years on their water heating bill

A solar PV water heating element system installed on a 200L geyser typically consists of 3 x 330W or 4 x 330W PV panels. If they are perfectly facing, we should in theory be able to get a maximum of about 5 hours of 990W out of the 3 x 330W panels (Annual average. Winter you will have less because the sunlight hours are less, and in summer, you will have more. This is unfortunately mismatched for when people use the most hot water). We therefore have a theoretical maximum of 4.95kWh but with panel temperature de-rating, first year ageing and MPPT losses the power available to the element will be around 4.2kWh/day.

The element controller will use Eskom to do the rest of the work and get the tank to 60°C (SANS 151 requires water to be stored at 60°C for Legionella disease prevention). The monthly Eskom bill for getting this system to 60°C will be R588. Assuming a 10% annual electrical tariff increase they will save R18731 over the next 5 years on their water heating bill.

For the 4 x 330W panel system the power available to the element will be around 5.6kWh/day. The monthly Eskom bill for getting this system to 60°C will be R504. Assuming a 10% annual electrical tariff increase they will save R24974 over the next 5 years on their water heating bill. The 3 x 330W panel system requires a north facing, unshaded roof space of 6m2 and the 4 x 330W panel system 8m2.

A large solar PV water heating element will save R24974 over the next 5 years on their water heating bill

A solar thermal water heater system typically installed on a 200L geyser consist of a 2.4m2 solar panel (flat plate or equivalent evacuated tube). From the TUV Rheinland test reports of the ITS 2.4m2 flat plate solar collector, it can be seen that it will give a thermal output of around 8.7kWh for the same 5 hours of annual average usable sunlight per day as used with the PV example above. De-rating this for differential temperature losses and 10m of installation piping we are left with 7.3kWh/day. The monthly Eskom bill for getting this system to 60°C will therefore be R402. Assuming a 10% annual electrical tariff increase they will save R32556 over the next 5 years on their water heating bill.

A solar thermal water heating system will save R32556 over the next 5 years on their water heating bill

A domestic hot water heat pump working at average South-African ambient temperatures will conservatively provide an annual average saving of 66% on whatever system it is connected to. The monthly Eskom bill for keeping this system at 60°C will therefore be R280. Assuming a 10% annual electrical tariff increase they will save R41609 over the next 5 years on their water heating bill.

A domestic hot water heat pump water heating system will save R41609 over the next 5 years on their water heating bill

Conclusions

The graphs below show the saving the different systems can provide for 150L, 200L and 300L hot water usage per day:

ITS 100L heat pump graph

ITS 200L heatpump graph

ITS 300L heatpump graph

 

An instantaneous gas water heater, in our view, makes sense in places where there is no electricity available. The completed installed cost of a proper unit is only a few thousand less than a flat plate with geyser and the saving from the solar system is almost double for 200L hot water usage. Gas water heating does not care about Eskom load-shedding, but do keep in mind that we have had gas supply shortages and that will leave you with cold water.

With storage water heaters, load-shedding is normally not a problem unless the outage lasts for more than a day since the water can stay warm in the tank for very long and re-heating using an electrical element or heat pump takes only a few hours. If you use 200L of 60°C water per day, 9kg of LPG will last you only 10 days and so you will have to think about the gas supply and logistics.

Instantaneous gas water heaters are also great backup for solar water heaters installed in locations with no electrical grid connection. The gas heater in such an installation will only cover the shortfall of the solar water heating system.

A solar PV water heating element, in our view, makes sense only when the geyser is situated far from the solar panels like in a multi-story building. The thermal losses in the piping of the normal solar thermal system in such an installation will reduce the output to such a level that the PV heating could be more cost effective. For standard installations where the geyser is within say 10m from the solar panel, the flat plate system will provide a much better return on investment.

A 3 x 330W installation is slightly more expensive than a 2.4m2 flat plate installation, but the flat plate will save R14k more over 5 years, in our example. Most solar PV element systems we see installed are completely undersized and are done by people who are simply trying to get away with the cheapest possible option.

A PV thermal system that will give you almost the same output power as a 2.4m2 flat plate will need 5 x 330W PV panels resulting in an expensive system that requires 10m2 of north-facing non-shaded roof space. Should the client at some stage want to install a PV electrical system to become more independent from Eskom, they will most likely not have enough roof space left.

Another great concern with PV element systems is the current lack of regulation of the installations and equipment. PV element systems operate at lethal DC voltages and installing one cheaply and poorly could potentially be deadly.

A solar thermal water heater system will provide a great return on investment, but it is important that it is installed correctly. Unfortunately, we are also seeing installers that are pushed for price going for undersized systems. If we for example look at the 200L system example using an ITS 2m2 flat plate collector your saving will be R26758 over 5 years. By going for the slightly bigger 2.4m2 flat plate, your installation cost will increase by about R400 but your saving over 5 years will increase by R5797 to R32556. A 2.4m2 flat plate is also by no means too big for a 150L system and so a 2m2 flat plate only makes sense for bigger systems where you require multiple panels.

A domestic hot water heat pump will provide the best saving in this example. An ITS 4.7kW heat pump installation will cost you about R5k more than an 2.4m2 flat plate installation but will result in a R9k better saving after 5 years.

A solar system can provide a bigger saving than a heat pump but for that the solar system needs to be oversized and water usage patterns needs to be adjusted. Typically you need double the volume of hot water that what you would need for a normal electrical geyser or a heat pump system. In coastal areas like Cape Town however the winter irradiation is much lower than summer irradiation. This means that even if your solar system was sized for 100% of your solar usage in summer you will have only about half the thermal output you need in the winter and the electrical element would need to do the rest. Winter is also when people use the most hot water and so a heat pump would almost always be a better solution in areas like Cape Town.

Solar PV and thermal systems can only “harvest” energy while the sun is shining. The system sizing is done to give you a certain percentage of your energy requirement per day which is based on how many liters of hot water you use per day. If some friends visit and stay over the extra hot water required will need to be heated using Eskom. With a heat pump system the heat pump will simply continue heating more water as you use more while providing around 66% saving on whatever you use.

To get the most out of solar PV and solar thermal heating systems also require you to use it correctly. If you then use most of the hot water in the evening, you will need Eskom to have hot water in the morning. If you are not using a lot of water in the morning, the solar system is heating a tank that is already almost on temperature and so you will not use all the energy available from your solar system during the day. With a heat pump, it makes no real difference when and how you use the water.

*This article was reproduced with permission from ITS Solar – South Africa’s Leading Heat Pump Supplier

Contact us today to assess, design and install your next energy efficient water heating and integrated renewable energy solutions:

ZPE ITS solar heat pumps

Landline: +2710 593 4449 | Whatsapp: +27605218388 | info@zpenergy.co.za | TW & IG: @zeropointSA | www.zpenergy.co.za

Zero Point Energy (Pty) Ltd is an accredited partner, installer and system integrator of the ITS range of industrial, domestic and pool heat pumps. Combined with our strong engineering and project management track record to date, this partnership enhances our value proposition to clients by allowing us to further optimise and broaden our integrated sustainability solutions offering.

We are also a proudly South African sustainable engineering company that provides professional engineering consulting & turn-key solutions in the areas of energy efficiency, renewable energy, off-grid and energy storage solutions, water efficiency and responsible waste management. The company is a 100% black youth-owned, 30% black female-owned company achieving a Level 1 BBBEE Contributor status, and has a passion to transform the energy industry without compromising on safety, quality and client satisfaction.  Learn more about the company’s team here

#heatpumps #energyefficiency #energysaving #costsaving #sustainability #greenenergy #renewableenergy #solarpower

floating solar

Potential of Floating Solar PV Plants in Southern Africa

Potential of Floating Solar PV Plants in South Africa

Over the last several years, large-scale solar PV plants have been installed to take advantage of the significant opportunity that solar power generation presents. Installations at this scale are happening internationally, regionally, as well as here in South Africa. Floating solar PV plants are a fairly new concept compared to the traditional ground-mount or roof-top solar PV plant setup. While interest and implementation of these systems are growing internationally, the local market is yet to fully tap and explore the tremendous benefits this configuration can bring.

floating solar

Source: ESI Africa

What Is a Floating Solar PV Plant?

A floating solar PV plant, as the name suggests, consists of a PV system floating on the surface of a water body. Most of the current applications of this emerging technology have used water bodies such as dams, quarry lakes, drinking water reservoirs, canals, and ponds.

The floating plant itself consists of a floating system or pontoon, which is the underlying structure and floating system upon which PV modules are installed. There is also a mooring system which fixes the floating system to a point at the bottom of the water body or anchored to the shore to prevent free movement. As with a solar land plant, there is also the solar PV DC cabling and power conversion equipment, and finally, AC cabling for power to be transferred to land. In this case, the cable can either be an underwater cable or a floating power line. The exact setup of the plant is determined by various factors such as water level fluctuations and wind load.

floating solar

Source: ESMAP

Between 2007 and 2014, several small-scale research floating solar PV plants were built, with the first one being in Japan in 2007. In 2008, California had the first commercial floating PV plant with a 175 kWp system. Floating solar PV plants are gaining traction, with Asia leading in installations. The floating solar market has tremendous potential to double the existing installed solar PV capacity by capitalizing on 400,000 square kilometers of man-made reservoirs globally by up to 400 GW. This is according to a World Bank Report called “Where Sun meets Water.”

Because the floating power plant is still in its infancy, industry standards and best practices are still in the works. DNV GL, an international accredited registrar and classification body, is at the forefront of a floating solar joint industry project working with stakeholders to develop a best practices guide by 2021.

Advantages of Floating Solar PV Plants

Why go through all the complexities of setting up a solar power plant on water? There are numerous advantages to this emerging application. Here are the main ones:

  • When existing water reservoirs are used, valuable land is freed up for other purposes such as for agricultural land or residential developments
  • Setting up a floating solar plant is a much faster and easier process. The process of land acquisition for developing a plant is often prolonged and complicated. Additionally, the installation itself takes longer to deploy as geotechnical studies and foundations are required for sub-surface conditions. Not having to do a large land installation is beneficial to soil and water conservation efforts.
  • A power plant on the surface of a water body results in reduced evaporation, which can be vital in areas where water is a scarce resource. This is a significant advantage to a water-scarce country like South Africa
  • The combination of hydropower and solar power plants is a cost-effective strategy for allocating new PV plants. Hydropower generation is increased by reduced evaporation, which has been a major challenge in these plants. Floating solar PV can increase the capacity factor of a hydropower plant by 50- 100%.
  • A floating solar power plant can generate more electricity than traditional ground-mounted and rooftop systems, about 7-14% more. This is because the water has a cooling effect, which reduces the operating temperature and increases the solar panel efficiency. Another possible contributor to the increased output is that there is less settled dust on the PV modules.
  • Floating plants can improve the quality of water by creating a sunlight barrier that prevents the photosynthesis and growth of algae in water bodies.
  • The cost of the solar mounting system is greatly reduced in a floating setup compared with land-based systems that require steel sub-structures and often concreted foundations.
  • It is much easier to wash the plant and its components in a floating system. Additionally, the large volumes of cleaning water used in a floating are reused, leading to operational & maintenance cost savings.
  • Floating PV plants are compatible with aquaculture and can be set up on an aquaculture reservoir or a fish pond, which benefits aquatic production.
  • Floating PV plants are attractive and can bolster the scenery and touristic appeal of an area.

Floating solar PV plants open up a world of possibility because they can be set up on any water bodies and greatly increase the solar power generation capacity. While the advantages of the floating system are numerous, large scale rollout does present its own unique set of challenges.

Strong winds can hamper floating PV panels. The mooring system must be strong enough to resist these. Stronger supports are being developed to address this challenge. In the long-term, further research will have to be done on the ecological impact on affected water bodies. Where saltwater is used, the damage from this must be evaluated. Finally, more information must be disseminated about the installation and maintenance of floating plants as well as best practices. As mentioned, a best practice guide is already in development, which is good news for the Southern African solar PV industry in the middle to long term.

floating solar

Source: Saur Energy

 

The Opportunity in Southern Africa

While the application of floating PV plants is fairly new, it continues to grow internationally. Many benefits can be achieved by adopting this technology in Southern Africa. In many parts of the country, water shortages and scarcity have affected normal living, especially in drought-affected areas like the Western Cape in South Africa. Floating power plants can be combined with water reservoirs to reduce evaporation losses.

Innovative solutions for the electricity generation challenges in the nation are always needed. Making using of the floating plant systems can scale up the rollout of solar PV and improve the output of hydropower stations. Floating plants are also a quicker route than the land acquisition channel, and they free up land for agriculture and other uses.

 

Contact Us

Contact the Zero Point Energy team to see how best we can help you make the move to reliable, renewable and self-sufficient energy.

Landline: +2710 593 4449 | Whatsapp: +27605218388 | info@zpenergy.co.za | TW & IG: @zeropointSA | www.zpenergy.co.za

Zero Point Energy (Pty) Ltd is a proudly South African sustainable engineering company that provides professional engineering consulting & turn-key solutions in the areas of energy efficiency, renewable energy, off-grid and energy storage solutions, water efficiency and responsible waste management. The company is a 100% black youth-owned, 30% black female-owned company achieving a Level 1 BBBEE Contributor status, and has a passion to transform the energy industry without compromising on safety, quality and client satisfaction.  Learn more about the company’s team here

ZPE ITS solar heat pumps

ZPE Partnership with ITS Solar – South Africa’s leading heat pump supplier

Energy efficient water heating solutions

In our continuous quest to revolutionize Africa’s sustainability, we are excited to announce our new partnership with South Africa’s leading heat pump supplier ITS.

Zero Point Energy is now an accredited partner, installer and system integrator of the ITS range of industrial, domestic and pool heat pumps. Combined with our strong engineering and project management track record to date, this partnership enhances our value proposition to clients by allowing us to further optimise and broaden our integrated sustainability solutions offering.

Water heating is often the highest energy consumer at most premises. Combining heat pumps into your integrated energy efficiency journey will result in a reliable, guaranteed and renewable approach to energy and cost savings.

 

ZPE ITS solar heat pumps

Contact us today to assess, design and install your next energy efficient water heating and integrated renewable energy solutions:

Landline: +2710 593 4449 | Whatsapp: +27605218388 | info@zpenergy.co.za | TW & IG: @zeropointSA | www.zpenergy.co.za

Zero Point Energy (Pty) Ltd is a proudly South African sustainable engineering company that provides professional engineering consulting & turn-key solutions in the areas of energy efficiency, renewable energy, off-grid and energy storage solutions, water efficiency and responsible waste management. The company is a 100% black youth-owned, 30% black female-owned company achieving a Level 1 BBBEE Contributor status, and has a passion to transform the energy industry without compromising on safety, quality and client satisfaction.  Learn more about the company’s team here

#heatpumps #energyefficiency #energysaving #costsaving #sustainability #greenenergy #renewableenergy #solarpower

tesla1

What You Should Know About the Tesla Powerwall 2 Energy Storage System

What You Should Know About the Tesla Powerwall 2 Energy Storage System

 

Source: Electrek

Tesla’s Powerwall 2 Battery System is a residential energy storage solution. It utilizes the company’s advanced lithium-ion battery technology as well as internet connectivity to deliver customers with a robust energy solution with wide applications in the smart home.

Most people know about Tesla from their pioneering work in electric vehicles. Beyond their automotive products, the company has expanded the applications of their battery technology to include residential and commercial energy storage products. Founded in 2003, the company continues to make strides towards its mission, which is “to accelerate the world’s transition to sustainable energy.” As the market for solar energy continues to grow, Tesla has also positioned itself and its products to maximize this clean and renewable energy source to solve energy problems around the world.

Source: CleanTechnica

 What is the Powerwall 2?

The Powerwall 2 Battery System or Powerwall 2 is the residential version of Tesla’s Powerpack energy storage product for commercial use. The pilot of the product was released in 2015 and the second generation was announced in 2016. Production takes place at the Gigafactory 1 in Nevada, USA.

The Powerwall 2 is an energy storage unit that can be mounted to a wall or to the ground. It is suitable for outdoor installation as it can handle temperature extremes on either end in the range of -20°C to 50°C, although the optimal range is between 0°C and 30°C. The unit is also water-proof. As you would expect from a Tesla product, the unit itself is designed very well and is also modern-looking. The slim product measures 1150 mm x 755 mm x 155 mm and weighs 122 kg.

Source: Tesla

The Powerwall 2 contains rechargeable lithium-ion batteries allowing the unit to store electricity from the grid or from an installed solar PV system. The applications of this product include solar self consumption, a backup power source during outages and for off the grid use.

Solar self-consumption is the act of using your solar energy to run devices within your home or business. Provided you have a net (aka bi-directional) energy meter, this will happen automatically when appliances are switched on in your home while your solar system is producing energy.

Lithium-ion batteries have a number of important advantages, making them the fastest growing battery technology on the market. For one, they are rechargeable. They have potential for high storage capacity and require very low maintenance. When new, these batteries do not require much priming. Compared with the widely used nickel-based batteries, lithium-ion batteries have half the self-discharge rate, meaning lower energy losses.

Energy is stored as DC power in the Powerwall 2 batteries and must be converted to AC power by the built-in inverter before it can be used by devices in the home. Each Powerwall has a usable capacity of 13.5 kilowatt-hours per unit, and for additional storage capacity, multiple units can be purchased and connected in parallel. The inverter also functions in the reverse to convert AC to DC power when the batteries are being charged. With a round-trip inverter efficiency of 90%, power lost in the trip to be stored in the unit and back out for usage equates to 10%.  The full owner’s manual contains the details of the product and its operation.

Connectivity and the Mobile App

 Along with the battery unit, comes the Powerwall Backup Gateway 2 which is the energy storage unit’s connection to the internet. This stays up-to-date with what is happening in the news, the area, and the weather concerning prices, policies, and any other factors that impact residential energy storage, particularly from solar PV systems. In the Tesla app, users of any of the company’s products from electric vehicles to storage units can keep track of key metrics and change a wide range of settings around how the product is used.

The Tesla app has impressive visuals and allows owners of the Powerwall 2 to:

  • View the current state of charge
  • Monitor energy flow (this happens between the Powerwall 2 and the rooftop solar PV units, the grid and the home appliances)
  • See detailed metrics and graphics for each energy source
  • Select between the different operating modes (Self-powered, Backup Only, Advanced Time-Based Control as well as special modes such as Grid Services, Storm Watch, and Preconditioning)

Source: Tesla

Advantages of the Powerwall 2

The Powerwall 2 is the energy-conscious resident’s answer to a self-powered home. There are a number of comparative energy storage solutions already on the market. With more and more people looking for backup solutions to withstand power outages and loadshedding, generators and other battery storage solutions are often used.

The Powerwall 2 is an investment that comes with some notable benefits. These include:

  • High energy storage capacity that can be combined with a solar PV system to reduce reliance on the grid in a self-powered home.
  • Energy stored from solar during the day is a great backup to power home at night or during loadshedding or an outage
  • The unit is well-designed and compact. It is safe for indoor or outdoor installation and allows easier integration because of its built-in inverter.
  • Although there is a high initial investment, it is worthwhile. You can reduce your monthly electricity bill.
  • Connectivity allows for over-the-air updates for new features and functions.
  • The Tesla app gives you more control and insight into your home energy use in real-time.

With the Powerwall 2, home owners can enjoy greater control over their energy use and withstand fluctuations in the grid power supply. Combining this storage unit with a solar PV system is a great choice that ultimately leads to monthly electricity bill savings as well.

Contact Us

tesla certified installer

As a Tesla Powerwall 2 certified Installer, use our free online Tesla system sizer and cost estimator here, or contact the Zero Point Energy team to see how best we can help you make the move to reliable, renewable and self-sufficient energy.

+27605218388 | info@zpenergy.co.za | @zeropointSA | www.zpenergy.co.za

Zero Point Energy (Pty) Ltd is a proudly South African sustainable engineering company that provides professional engineering consulting & turn-key solutions in the areas of energy efficiency, renewable energy, off-grid and energy storage solutions, water efficiency and responsible waste management. The company is a 100% black youth-owned, 30% black female-owned company achieving a Level 1 BBBEE Contributor status, and has a passion to transform the energy industry without compromising on safety, quality and client satisfaction.  Learn more about the company’s team here

 

tesla powerwall2 zero point energy

Zero Point Energy now a Tesla Powerwall 2 Certified Installer in South Africa

The Team at Zero Point Energy is excited to announce that we have recently been vetted, trained and accredited by Tesla as a Tesla Powerwall Certified Installer for South Africa.

You can rely on Powerwall to reduce your reliance on the grid and to power your home with renewable energy that you control.

With increased Eskom load shedding and electricity tariff increases, combined with solar PV and battery technology improvements and cost reductions, there is no better time to consider solar and energy storage for your home!

Utilise our free online Tesla Powerwall 2 system sizer to get an indicative cost here , or contact us at teslapowerwall@zpenergy.co.za for any technical or pricing queries.

#energystorage #solarpv #renewableenergy #tesla #powerwall2 #batterystorage #lithiumion #southafrica

CESA

ZPE achieves Consulting Engineers South Africa (CESA) Membership

Zero Point Energy has been granted Professional Electrical Engineering Membership of Consulting Engineers South Africa (CESA).

CESA is the custodian of well-being in the South African consulting engineering industry, with members compelled to subscribe to upholding the integrity of the industry by adhering to a professional code of ethics providing quality and cost effective professional consulting engineering services.

Niche engineering credentials

As one of only 3x EME electrical consulting engineering firms in the country that have 100% black and considerable female ownership, we are proud of this empowering achievement to date. Beyond this, we strive to maintain and improve upon our quality & customer-centered electrical consulting engineers and project management services to our valued clients.

Contact us at info [at] zpenergy.co.za for more information or to get in touch for your next project

#CESA #engineering #professionalengineer #consultingengineering #PrEng #electricalengineering #consultingengineers

zpe consulting engineering

ZPE Pan-African Solar PV & Battery Storage Engineering & Design Consulting Services

Zero Point Energy has executed over 30x engineering & design packages for Africa-focused solar PV and micro-grid developers & IPPs over the past 6 years. We have helped our clients with concept designs, detail designs, successful utility & municipal approvals, as well as to win competitive private & public sector tenders.

We achieve this by keeping up to date with latest industry trends, technologies & optimally designing solutions that are localised and customised for sub-Saharan Africa. This includes projects in South Africa, Botswana, Namibia, Mozambique and Zambia.

zpe consulting engineering

Example of a 5MW utility-scale solar PV plant yield simulation study. Also indication of location of projects we’ve done engineering designs for

Solar PV & Battery Storage Consulting Engineering Service Offering:

Our service offering across utility-scale, commercial & industrial solar PV and Li-On battery storage projects include:

  • PVSyst, PVSol, & Homer Pro design simulation studies
  • Design of utility scale (>1MW), commercial, industrial & agri-sector (50 kW – 999kW), and large residential solar PV installations encompassing ground-mount fixed-tilt and single-axis tracker systems, rooftop & solar carport projects, and containerised lithium-ion battery systems
  • Energy resource, bankable yield simulation studies, 3D shading investigations, & related techno-economic assessment reports & studies
  • DC stringing length & routing optimisation studies, solar PV earthing designs, panel & MPPT layout optimisation, solar PV AC tie-in design & specification, battery system integration design, solar PV & diesel generator integration designs
  • Electrical single line diagrams, detailed plant GA layout drawings, power system simulation studies, key equipment selection & specification, overhead line and substation design
  • Utility interconnection applications, municipal SSEG applications & sign-off, and electricity tariff analysis
  • Development of bill of quantities, project schedules, project cost estimates, and other project deliverables as required

 

Accreditations, Experience & References:

  • Engineering Council of South Africa (ECSA) Professional Electrical Engineers (Pr.Eng) certified electrical engineers, ISO 9001-aligned QMS design processes, professional CAD capabilities and document control
  • Team has over 30 years combined experience working on wide spectrum of solar PV projects in South Africa and in Africa including the REIPPPP, mining, industrial & agri sectors. Read more about the the team here.
  • We have professional indemnity insurance cover up to R5 000 000 & are Consulting Engineers South Africa (CESA) accredited consulting engineering company
  • We are a proudly South African Level 1 BBBEE contributor with 100% black-ownership and 41% female ownership
  • Check out our track record of proven and completed projects here: ZPE Completed Projects

Contact us today to see how we can assist your team succeed on your next solar PV and/or battery system project: info@zpenergy.co.za +27605218388 @zeropointsa

 

Design Drawing Examples:

Below an example of an 11kV MV switchyard feeder bay design for the export of solar power from a 2MW solar PV plant in Swaziland

solar substation HV GA

An example of a scaled CAD layout  of a 5MW solar PV plant we designed in Botswana with optimised location of solar panel trackers, inverter locations, perimeter roads, substation and access points

solar PV layout drawing

Below an example of an 11kV main substation electrical single line diagram (SLD) accumulating power from the field inverter stations via ring main units (RMUs)  for a 10MW solar PV plant in South Africa,  and exporting power via an 11kV overhead line tie-in to utility substation

solar PV SLD

#engineering #design #solarpv #energystorage #africa #CAD #pvsyst #homer #pvsol #SLDs #electricalengineering

battery solar container

Custom Containerised Solar PV + Battery Storage Solutions for Africa

Custom Containerised Solar PV + Battery Storage Solutions for Africa

Our custom-designed solar PV & battery storage containerised solutions are engineered for Africa, but designed & built locally in Johannesburg.

This current pair of retro-fitted shipping container systems were designed for AC-coupled solar PV minigrid integration, taking our electricity-intensive client off-grid using advanced lithium-ion battery technology and top tier inverter, solar and monitoring equipment with lifespan guarantees ranging from 10 to to 25 years.

In addition to being designed as a plug-and-play system once dropped down at any urban or rural site, we’ve spec’d these units to have remote monitoring capability, thermal insulation, on-site access security control, alarm & fire prevention systems, small power & lighting, comprehensive earthing as well as air-conditioning.

Civil site works currently underway to allow deployment next week. Our team is looking forward to testing & commissioning these systems!

 

battery solar container

#Africa #renewableenergy #energystorage #solarPV #containers #minigrid #offgrid #ruralelectrification #design #engineering #johannesburg #electricity #batterystorage #lithiumion

victron residential post covid

First Post COVID-19 Lockdown Installation

First Post COVID-19 Lockdown Installation

Our first Level 3 residential battery backup system completed post lockdown in South Africa. Good to be back on sites again helping our customers take control of their electricity supplies and to beat any imminent load shedding.

This system was designed to include a top-of-the-range 6.5kW battery inverter and 10.5kWhr of lithium-ion batteries, sufficient to run a 4 bedroom house for well over 12 hours, with battery life guaranteed to last over 10 years.

Also includes remote monitoring to control and visualize energy usage from the palm of our client’s hand via a mobile app interface.

victron residential post covid

#eskom #covid19 #batterystorage #inverter #victronenergy #lithiumionbatteries #loadshedding