Solar Solutions

Solar On Grid Systems (Net metering)

Grid-tied, on-grid, utility-interactive, grid inter tie and grid back feeding are all terms used to describe the same concept – a solar system that is connected to the utility power grid.
 
Net Metering is an electricity policy for utility customers who operate their own on-site “self-generation” power systems such as photo voltaic systems. PV systems are connected to the utility grid via the customers’ main service panel and meter and, when generating more power than is needed at the site, return excess electricity to the grid through the power meter, reversing the meter from its usual direction.
As a result of the meter working in both directions – one way to measure power purchased (when on-site demand is greater than on-site power production), the other way to measure power returned to the grid – the customer pays the “net” of both transactions.
Save More Money
Generate More Electricity
Utility Bill
Electrical Utility As backup
No Maintenance
Advantages of Grid-Tied Systems
 
1. Financial Credit for Extra Solar Power Produced.
 
A grid-connection will allow you to save more money with solar panels through better efficiency rates, net metering, plus lower equipment and installation costs:
 
Batteries, and other stand-alone equipment, are required for a fully functional off-grid solar system and add to costs as well as maintenance. Grid-tied solar systems are therefore generally cheaper and simpler to install.
 
Your solar panels will often generate more electricity than what you are capable of consuming. With net metering, homeowners can put this excess electricity onto the utility grid instead of storing it themselves with batteries.
 
Net metering (or feed-in tariff schemes in some countries) play an important role in how solar power is incentivized. Without it, residential solar systems would be much less feasible from a financial point of view.
 
Many utility companies are committed to buying electricity from homeowners at the same rate as they sell it themselves.
 
2. The utility grid is a virtual, No Battery Storage System Needed.
 
Electricity has to be spent in real time. However, it can be temporarily stored as other forms of energy (e.g. chemical energy in batteries). Energy storage typically comes with significant losses.
 
The electric power grid is in many ways also a battery, without the need for maintenance or replacements, and with much better efficiency rates. In other words, more electricity (and more money) goes to waste with conventional battery systems.
 
Additional perks of being grid-tied include access to backup power from the utility grid (in case your solar system stop generating electricity for one reason or another). At the same time you help to mitigate the utility company`s peak load. As a result, the efficiency of our electrical system as a whole goes up.
 
3. No Backup Generator for when Solar Power is Not Available
 
Another expensive part of early solar power systems that you won’t need is the backup generator. Generators are expensive, noisy and need fuel (gasoline, diesel, natural gas or propane). The electrical utility is there as your backup when solar power is not available.
 
4. Seasonal Storage – Solar Power Produced in Summer Saves on Winter Costs
 
One of the frustrations of off-grid systems which are not connected to the utility is that the extra power in the summer months can’t be stored for the winter. Battery banks typically store power for only 3-5 days. When the batteries are full there is no way to store the extra energy. But, with net metering, you are feeding back your power over the summer and you get credited for it in the winter – now you have seasonal storage.
 
5. No Maintenance – Solar Power without Hassles
 
Handy system with net metering, we have now eliminated the batteries and the backup generator – the two components of a solar power system that require maintenance and have the shortest lifetimes. The only components you need for a grid-tied net metering system is the solar panels, which produce the power, and an inverter that converts the DC power from the solar panels to the standard AC power produced by the utility. Neither of these components requires maintenance. The solar panels, which have a 25 year warranty, are made from a semiconductor material and usually protected by a tempered glass front. The inverters, some of which also have 25 year warranties, are solid state and also maintenance free.
 
A grid-tied net metering system gives you the advantages of producing your own clean renewable energy without maintenance hassles and with very durable components.

Solar Hybrid System

When choosing a solar power system, most households and businesses choose either a grid-connected or an off-grid system.
But there’s a third option. A hybrid solar system combines the best of both worlds: the convenience of a grid connected system — including the ability to earn Feed-In Tariff credits with the extra peace of mind of a battery backup. This means that even during a power blackout, you still have electricity.Combining energy storage with a grid connection to your property, hybrid systems can provide the flexibility of being able to store the energy you generate during the day instead of feeding it back into the grid – typically at a low feed-in tariff. This energy can then be used in the evening instead of buying power back at a higher price.
Providing Uninterruptable Power
Outsmart The Utilities
Programmable
Grid Support
Peak Lopping
Advantages of Solar Hybrid Systems
  • Providing Uninterruptable Power
  • Buying a hybrid system from Going Solar will mean that when the grid fails, your system will keep going. Our hybrid systems are able to disconnect from the network in the event of a grid interruption (when a standard solar system would shut down). You will be able to continue to run certain appliances from your batteries (and solar during sunlight hours).
  • Allowing you to outsmart the Utilities
  • A hybrid system can ‘load shift’ as shown in the figure below. This means that the energy that you generate during the day is not wastefully fed back into the grid with minimal financial return to you. The energy is stored and can be used in the evening or whenever you like.
  • Hybrid Systems are fully programmable
  • An advantage of hybrid systems is that they are able to control and balance the available sources of energy:
  • If the power generated by a solar array is insufficient to supply daytime loads as well as charge your batteries, the system can recharge your batteries from the grid when a lower off-peak electricity rate is available.
  • When your electricity usage goes above a certain level, electricity companies may charge you at a higher rate for this increased level of demand. Hybrid systems can provide ‘peak lopping’ where some stored power can be drawn from the batteries to help balance the power usage.
  •  ‘Grid support’ can also be provided by your hybrid system if your grid connection does not have the capacity to supply a load. The hybrid system could supply the extra power. And this may allow you to avoid a costly mains upgrade to your property.

Solar Pumping Systems

Solar water pumping system is a stand-alone system operating on power generated by Solar Photovoltaic panels.

The power generated by solar panels is used for operating DC surface centrifugal mono-block pump set for lifting water from open well or water reservoir for minor irrigation and drinking water purpose. The system requires a shadow-free area for installation of the Solar Panels.
 
This opportunity lies in two areas:
  • Stock and domestic pumping
  • and Bulk water pumping for irrigation.

Whether your pumping task is large or small, it is important that you approach solar from an informed position. Typically, diesel-powered pumps are used in areas where connecting to the electricity grid is difficult. Solar photovoltaic (PV) systems can be an attractive complementary energy source deployed alongside diesel pumps in areas with plenty of sunshine and where the cost to run power lines is high.

Scalable
Best Suited For Transfer Operatios
Stock Pumpin
Distributed PV
Compliment Diesel Pump

Photovoltaic systems have the benefit of being scalable, with capacity ranging from a few watts for applications such as automated farm gates or timers to hundreds of kilowatts for the homestead and farm sheds. Rather than having one large centralized system, a number of distributed PV systems can be deployed at pump sites.

Solar pumping systems are best suited for transfer operations (to pump water out of bore, for instance, or transfer it from dam to storage tank) in which pumps run continuously for most of the day.

Applications that require water to be pumped at night are not as well suited to solar-powered pumps, as storage solutions such as batteries and storage tanks can add significantly to the cost of the system. Although these energy storage solutions can be expensive, they allow for greater utilization of the PV system. Depending on the application, stocked water can be fed by gravity when there is insufficient sunlight to power the solar pumps, thus reducing diesel consumption further.

Due to the high capital costs that are still associated with solar systems, simple paybacks of seven to eight years are generally achievable only where pumping currently occurs for more than half the year. These costs are expected to reduce over the coming years as price reductions occur within the solar PV and commercial battery storage industries.

How does it work?

A typical solar-powered pumping system consists of solar panels connected to an electric motor that runs a bore or surface electric pump. A solar pumping solution available from your irrigation supplier will typically supply a DC (mains-powered) pump that is connected directly to the solar panel and does not require a DC/AC inverter. DC brushless motors also offer very high efficiency levels (over 90 percent). In cases where an AC (battery-powered) pump is already in place, an inverter is required between the PV panel and the motor to convert from the direct current generated by the solar panel to the alternate current required by the electric pump motor.

In the case of a solar-diesel hybrid system, a solar pumping system (PV panel plus pump) is installed to complement the existing diesel pump operation. The solar pump can either pump directly into the system to offset diesel pump operation during daytime, or pump water to a storage tank or reservoir (which is part of the solar pumping solution) so that water is also available on cloudy days and at night. This is illustrated in the figure below.

Key steps in sizing a solar pumping system

  • Determine the total dynamic head (TDH) of the system using flow-rate requirements (L/min), pipe length and diameter, and height between suction and discharge points. TDH = static head + dynamic head (line friction).
  • Determine the daily flow (m3/day) requirement and the expected number of weeks per year of pumping.
  • Depending on the water source, choose a surface or submersible (bore) pump.
  • Using manufacturer pump curves, select a pump of adequate size to meet head and flow requirements.
  • Knowing the power requirement and running time for the selected pump, determine the electrical load profile of the pumping operation to then size the solar PV system.
  • Refer to supplementary paper, solar photovoltaics.
  • Ascertain the capacity of the storage dam or tank by determining the flow rate the process requires and the storage time, which equals the amount of time outside daylight hours for which the pump normally runs. Consider using battery storage or combinations.

Solar Street Light

solar street lights are powered by PV panels, in-built battery, LED lights and smart sensors, all integrated into a single compact unit.
 
Solar LED street lights have emerged as a cost-effective and environment-friendly to light up roads and public spaces. LED lights are widely acknowledged for energy conservation, are long-lasting and good-looking, and are maintenance-free. These characteristics make LED-base solar street lights well-suited for commercial as well as domestic lighting applications.
 
The solar street light does not need to set up the transmission line or route the cable, and no any special management and control are required. It can be installed in the entire public place such as the square, the parking lot, the campus, the street or the highway etc. The street lighting is closely related to people’s daily life. Following quick development in process of the global urbanization, the green, efficient, and long-life LED light gradually enters into our lives.
 
A good LED street lighting system is characterized with high efficiency, energy-saving, long-life, high color rendering index and environmental protection, which not only has a great significance on energy-saving of the city lighting , but also has close relationship with people’s health and the economic development. 
Save More Money
Independent of utility company
Wireless In Nature
No threat
Zero Maintenance
Unending Benefits
  • Due to off-grid nature of solar street lights, solar street lights incur minimal operational costs.
  • Such lights are wireless in nature and are independent of the utility company. Compared to conventional street lights, solar street lights require almost zero maintenance. Due to the absence of external wires, these lights do not pose any threat of accidents like electrocution, strangulation and overheating. Infact, solar lights illuminate the streets throughout the night irrespective of power cuts and grid failures.
  • Solar street lights are a delight for environmentalists around the world as it can provide significant lowering of carbon footprint of individuals, homes and businesses.
  • In other words, solar-powered lights are a perfect green lighting solution.

Solar Gysers

Solar water heaters — also called solar domestic hot water systems — can be a cost-effective way to generate hot water for your home. Just like any other big purchases made for your home, its important when buying a solar geyser that you understand what you’re paying for, and how it will benefit you in the long run. They can be used in any climate, and the fuel they use — sunshine — is free. Solar water heating systems include storage tanks and solar collectors. There are two types of solar water heating systems: active, which have circulating pumps and controls, and passive, which don’t.

There are two types of active solar water heating systems:
  • Direct circulation systems

Pumps circulate household water through the collectors and into the home. They work well in climates where it rarely freezes. The water moves through the solar collector and then directly into the geyser with the assistance of electrical pumps and controls. If not, it can be done via a natural thermosiphoning

  • Indirect circulation systems
Pumps circulate a non-freezing, heat-transfer fluid through the collectors and a heat exchanger. This heats the water that then flows into the home. They are popular in climates prone to freezing temperatures. Unlike the direct solar water geyser, the indirect solar water geyser has a solar collector that transfers a heat transfer fluid such as antifreeze. Thereafter, the antifreeze flows through the heat exchanger, which is surrounded by water. The water receives the heat from the antifreeze (but never mixes with it).
Cost Effective
Use Free Fuel
Work Well
No threat
Zero Maintenance
Internal workings of solar water geysers
Solar water geysers rely on warm water rising, better known as convection. This is how water circulates through the panels. Convection happens when the water stored in the panels heats up and rises into the water tank above, or in the ceiling – depending on where you decide to install it. The hot water in the tank then moves into the cylinder, usually located inside the house.
Meanwhile, the cooler water in the tanks flows downwards into the absorber (collector). These actions create circulation.
If the solar geyser is in the ceiling and at a lower level than the panels outside on the roof, then convection will not take place and a circulating pump is required to circulate the water between the tank and panels.

Solar Pump Inverters

The pumping inverter controls and regulates the operation of the system, transforms the direct current of solar cell array into alternating current to drive water pump. In addition, according to the change of sunlight intensity, regulate output frequency timely, to realize MPPT (Maximum Power Point Tracking). The water pump is driven by Single-phase AC motor. It pumps water from deep well, river, and lake, then inject water into water storage tank/pool, or directly connect with irrigation system or fountain system, etc. According to actual requirements of system and installation, different types of water pumps such as centrifugal pump, axial flow pump, mixed-flow pump, or deep-well pump can be used.

Product Characteristics:
  • Use independently-developed dynamic VI MPPT (Maximum Power Point Tracking) control method. The response speed is fast. Operation is stable and reliable.
  • It solves the following problems: tracking effect is poor when sunlight intensity rapidly; operation is not stable; water hammer damage.
  • All digital control. It has complete automatic operation, data storage, and complete protection functions.
  • Solar Pumping Inverter is specially designed for solar water pump. The inner structure is more reasonable and professional.
  • All key parts used in solar pumping inverter are made by international famous brands. The quality is reliable, service life is long, and quality assurance period is long.
  • The shell of solar pumping inverter is thick. The design process is improved through abrasive tool test for many times. The appearance is elegant and exquisite, model is compact, and weight is proper.
  • solar pumping inverter integrates combiner box. It includes DC switch, lightning arrester, fuse, and optional components. It greatly simplifies and facilitates equipment installation and maintenance, but also effectively protects the equipment.

Solar Hybrid Inverters

In the context of residential solar storage systems, a hybrid inverter (sometimes referred to as a multi-mode inverter) is an inverter which can simultaneously manage inputs from both solar panels and a battery bank, charging batteries with either solar panels or the electricity grid (depending on which is more economical or preferred). Their capabilities may go beyond this however – some devices also handle inputs from wind turbines, generators and other power sources.

Hybrid inverters can vary in size, performance and features. Most models usually operate bi-directionally, meaning they can convert DC power from modules to usable AC power and then convert stored AC from the batteries to power loads when needed. Hybrids can also remain grid-connected and use a mix of renewable and non-renewable energy to charge batteries and offset loads.

  • All-in-one inverter solution for grid-connected solar-plus-storage systems
  • Frequently intelligent and programmable for maximizing overall system efficiency and savings
  • Can usually be installed without batteries for future expansion
  • Long history of use in off-grid and stand-alone power systems

Batteries

A battery is a portable energy source that converts chemical energy to electrical energy. Simply put, batteries contain three basic parts: the electrodes, the electrolyte and a separator. There are always two electrodes in a battery: the cathode is connected to the positive end, while the anode is connected to the negative end. When the battery powers a load, it discharges, and current flows from the cathode to the anode. When the battery charges, current flows from the anode to the cathode.
Electrodes are immersed in an electrolyte, a liquid or gel substance that contains the electrically charged ions that react with the electrodes. This chemical process causes the battery to generate electricity. The separator physically separates the electrodes. Without it, the electrodes would come into contact and be short-circuited, destroying the battery.
Portable
Lead Acid
Nickel Cadium
Deep Cycle Storage
Cost Effective
Batteries provide electricity in the form of direct current (DC), but an inverter can be used to achieve alternating current(AC). The most important parameters of any battery are the following:Nominal cell voltage
  • Nominal cell voltage
  • Nominal capacity
  • Battery type
  • Number of cells in the battery string
There are three main types of rechargeable batteries: lead-acid, nickel-cadmium (NiCd) and lithium-ion.
What’s a Good Battery for Solar Energy Systems?
Deep-cycle storage capability is a mandatory feature for batteries in a solar energy system. Lead-acid batteries have this feature, as they can be discharged up to 80 percent of total capacity without any repercussions. Flooded lead-acid batteries are the most commonly used batteries in solar energy systems, as they also have a long lifespan and are cost-effective.

Solar On-Grid Inverters

Photovoltaic solar systems generate DC voltage, and an inverter converts the power to AC voltage. Solar inverters produce a sine wave and are designed for high power—up to hundreds of kilowatts. Unlike simple electronics inverters, solar inverters provide numerous functions in addition to DC-to-AC conversion. They are responsible for energy metering, monitoring, regulation and protection of the solar energy system.
 
Solar energy systems can be designed as on-grid or off-grid (isolated) systems. Off-grid systems are designed to work independent of the electrical network, while on-grid systems can supply energy to the network. On-grid systems can be set up with or without a battery storage system, which can be used for backup power. Inverters are a mandatory component in both types of systems.
Energy in a solar energy system can flow in different directions. In the case of a simple system in a home application, the users can be supplied only from PV panels. If there is insufficient sunlight, the users can be supplied from both PV panels and batteries, or only from the batteries (e.g., during the night).
Solar Charge Controller
Protection
Safety
Energy Metering
Cost Effective
A very important function of solar inverters is their role as the solar charge controller. Depending on the energy state of the PV panels, the solar inverter will direct energy to users, battery charging or the network. The charge controller connects the PV panels, batteries and users, but also protects the battery from overvoltage and deep discharging. The battery voltage is adjusted automatically depending on the battery type, condition and temperature, while the user supply voltage must be constant.
 
Another important task of the solar inverter is providing protection and safety. This is especially important in on-grid systems, as there are strict regulations when a solar system is connected to the network. In this case, the inverter must synchronize the voltage and frequency of the solar plant to the network. It also must synchronize any disconnections from the network during outages, as it can be problematic if the solar system continues to supply energy even though the power grid is no longer in place. This is called islanding, and it can be dangerous to workers who may come in contact with powered circuits. Solar inverters should be able to detect islanding and disconnect the solar system from the circuit—a feature called anti-islanding.