- Energy Saving Options
- Grid Tie & Hybrid Systems
- Advantages of Grid-Tied Systems
- Advantages of Off-Grid Solar Systems
- Advantages of Hybrid Solar Systems
With our partner we are able to offer 3 main services regarding energy saving solutions:
- Energy Audits and LED light solutions
- Grid Tie Solutions for your home or Business
- Hybrid Solar solutions for your Home or Business
- A home energy checkup, helps owners determine where their house is losing energy and money – and how such problems can be corrected to make the home more energy efficient. We visit your home and do a full checkup. Items shown here include looking at your lighting, checking your geyser/s and fitting an energy monitor to your main DB board for a week to see how much energy you are consuming in the home.
- A home energy audit, also known as a home energy assessment, is the first step to assess how much energy your home consumes and to evaluate what measures you can take to make your home more energy efficient. An assessment will show you problems that may, when corrected, save you significant amounts of money over time.
The main areas that we focus on are the following:
- Lighting throughout the house, namely the downlighers and normal bulbs present as well as the outside flood lights that can be converted to LED
- The number of geyser in your home and if they can be converted to Solar or Heatpump assisted units to limit their energy consumption
- The viability of fitting a small Grid Tie / Hybrid Solar system to generate your own power so as to limit your reliability on ESKOM.
- The option of fitting a battery backup system to offer convenience in the times of Load shedding.
Grid-Tied, Off-Grid and Hybrid Solar Systems
What are the benefits of grid-connected solar panels vs. living off the grid? Deciding whether or not to grid-tie your solar panels is usually pretty straightforward – the clear-cut benefits of being grid-tied appeals to the majority of homeowners. There are, however, some people that choose to live off the grid.
What would be the best in your situation? Let`s look closer at the benefits of each system namely grid tied, off-grid and hybrid solar systems.
Grid-Tied Solar Systems
Grid-tied, on-grid, utility-interactive and grid back feeding are all terms used to describe the same concept – a solar system that is connected to the utility power grid.
- Save more money with net metering 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 choose put this excess electricity onto the utility grid instead of storing it themselves with batteries. Please note that not all provinces allow this and there is a monthly surcharge applied together with a special bi-directional meter that needs to be installed.
- The utility grid is a virtual battery 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.Lead-acid batteries, which are commonly used with solar panels, are only 80-90% efficient at storing energy, and their performance degrades with time. Additional perks of being grid-tied include access to backup power from the utility grid (in case your solar system stops 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.
Equipment for Grid-Tied Solar Systems
There are a few key differences between the equipment needed for grid-tied, off-grid and hybrid solar systems.
Standard grid-tied solar systems rely on the following components:
- Grid-Tie Inverter (GTI) or Micro-Inverters
- Power Meter
- Solar panels
- Sub DB for essencial circuits
- Energy efficient LED lights to be installed
- Solar Geyser to be present
- Gas stove for cooking and heating
Grid-Tie Inverter (GTI)
What is the job of a solar inverter? They regulate the voltage and current received from your solar panels. Direct current (DC) from your solar panels is converted into alternating current (AC), which is the type of current that is utilized by the majority of electrical appliances.In addition to this, grid-tie inverters, also known as grid-interactive or synchronous inverters, synchronize the phase and frequency of the current to fit the utility grid (nominally 50Hz). The output voltage is also adjusted slightly higher than the grid voltage in order for excess electricity to flow outwards to the grid.
Micro-inverters go on the back of each solar panel, as opposed to one central inverter that typically takes on the entire solar array.Micro-inverters are certainly more expensive, but in many cases yield higher efficiency rates. Homeowners who are suspect to shading issues should definitely look into if micro-inverters are better in their situation.
Most homeowners will need to replace their current power meter with one that is compatible with net metering. This device, often called a net meter or a two-way meter, is capable of measuring power going in both directions, from the grid to your house and vice versa.You should consult with your local utility company and see what net metering options you have. ESKOM issues a power meter at a fee and pays you a set fee per kw.h for the electricity you generate as well as a monthly admit fee.
Off-Grid Solar Systems
An off-grid solar system (off-the-grid, standalone) is the obvious alternative to one that is grid-tied. For homeowners that have access to the grid, off-grid solar systems are usually out of question. Here`s why:To ensure access to electricity at all times, off-grid solar systems require battery storage and a backup generator (if you live off-the-grid). On top of this, a battery bank typically needs to be replaced after 10 years. Batteries are complicated, expensive and decrease overall system efficiency.
- No access to the utility grid Off-grid solar systems can be cheaper than extending power lines in certain remote areas.Consider off-grid if you don’t have access to ESKOM power as its to far away OR if you want to be completely self sufficient and not have to rely on the utility at all. The costs of overhead transmission lines can range from thousands per km (for rural construction) to hundreds of thousands per km (for urban construction).
- Become energy self-sufficient Living off the grid and being self-sufficient feels good. For some people, this feeling is worth more than saving money. Energy self-sufficiency is also a form of security. Power failures on the utility grid do not affect off-grid solar systems.On the flip side, batteries can only store a certain amount of energy, and during cloudy times, being connected to the grid is actually where the security is. You should install a backup generator to be prepared for these kinds of situations.
Equipment for Off-Grid Solar Systems
Typical off-grid solar systems require the following extra components:
- Solar Charge Controller
- Battery Bank
- DC Disconnect (additional)
- Off-Grid Inverter
- Backup Generator (optional)
- Energy efficient lighting
- Solar geyser
- Energy wise appliances with low power consumption
Solar Charge Controller
Solar charge controllers are also known as charge regulators or just battery regulators. The last term is probably the best to describe what this device actually does: Solar battery chargers limit the rate of current being delivered to the battery bank and protect the batteries from overcharging.
Good charge controllers are crucial for keeping the batteries healthy, which ensures the lifetime of a battery bank is maximized. If you have a battery-based inverter, chances are that the charge controller is integrated.
Without a battery bank (or a generator) it’ll be lights out by sunset. A battery bank is essentially a group of batteries wired together. You get various type of batteries but the most common is GEL type batteries which can be charged and decharged many times in their lifetime.
DC Disconnect Switch
AC and DC safety disconnects are required for all solar systems. For off-grid solar systems, one additional DC disconnect is installed between the battery bank and the off-grid inverter. It is used to switch off the current flowing between these components. This is important for maintenance, troubleshooting and protection against electrical fires.
There`s no need for an inverter if you`re only setting up solar panels for your boat, your RV, or something else that runs on DC current. You will need an inverter to convert DC to AC for all other electrical appliances.
Off-grid inverters do not have to match phase with the utility sine wave as opposed to grid-tie inverters. Electrical current flows from the solar panels through the solar charge controller and the bank battery bank before it is finally converted into AC by the off-grid-inverter.
It takes a lot of money and big batteries to prepare for several consecutive days without the sun shining (or access to the grid). This is where backup generators come in.
In most cases, installing a backup generator that runs on diesel is a better choice than investing in an oversized battery bank that seldom gets to operate at it`s full potential. Generators can run on propane, petroleum, gasoline and many other fuel types.
Backup generators typically output AC, which can be sent through the inverter for direct use, or it can be converted into DC for battery storage.
Hybrid Solar Systems
Hybrid solar systems combine the best from grid-tied and off-grid solar systems. These systems can either be described as off-grid solar with utility backup power, or grid-tied solar with extra battery storage.
If you own a grid-tied solar system and drive a vehicle that runs on electricity, you already kind of have a hybrid setup. The electrical vehicle is really just a battery with wheels.
- Less expensive than off-gird solar systems
Hybrid solar systems are less expensive than off-grid solar systems. You don`t really need a backup generator, and the capacity of your battery bank can be downsized. Off-peak electricity from the utility company is cheaper than diesel.
- Smart solar holds a lot of promise
The introduction of hybrid solar systems has opened up for many interesting innovations. New inverters let homeowners take advantage of changes in the utility electricity rates throughout the day.
Solar panels happen to output the most electrical power at noon – not long before the price of electricity peaks. Your home and electrical vehicle can be programmed to consume power during off-peak hours (or from your solar panels).
Consequently, you can temporarily store whatever excess electricity your solar panels in batteries, and put it on the utility grid when you are paid the most for every kWh.
Smart solar holds a lot of promise. The concept will become increasingly important as we transition towards the smart grid in the coming years.
Equipment for Hybrid Solar Systems
Typical hybrid solar systems are based on the following additional components:
- Charge Controller
- Battery Bank
- DC Disconnect (additional)
- Battery-Based Grid-Tie Inverter
- Power Meter
Battery-Based Grid-Tie Inverter
Hybrid solar systems utilize batter-based grid-tie inverters. These devices combine can draw electrical power to and from battery banks, as well as synchronize with the utility grid.
The bottom line is this: Right now, for the vast majority of homeowners, tapping the utility grid for electricity and energy storage is significantly cheaper and more practical than using battery banks and/or backup generators.