Residential Emergency Generators
Portable Emergency Generators
Portable Emergency Generators are the type that are used by contactors for jobsite power, and also some home owners who just don't want to absorb the cost of a completely automatic and permanent installation. The Portable units are usually "gasoline" powered engines and the output power capacity is in the range of 1 KW to 17.5 KW. These units are excellent for a remote cabin or use during the occasional storm outage, but most are totally manual switch-over and/or limited run time based on engine type and fuel. A.R.&E. does NOT sell or service this type of generator but can offer some limited recommendations of size and brand based on past service history and customer feedback. We can also give you a recommendation of "sizing" after a discussion with you about your possible load criteria. Give our sales team a call or use this link to access our contact page.
Stationary Mounted Emergency Generators
The Stationary Mounted Emergency Generator is the ultimate solution for your comfort and security "when the lights go out". A residential emergency generator of this type is mounted on a solid base, permanently wired to your home electrical panel through an "ATS" (Automatic Transfer Switch), and connected to a fuel source based on the engine specs. When the utility power is lost to your home, the transfer switch senses the loss, starts the emergency generator and switches the electrical load to the emergency source... your generator. When the utility power resumes, the ATS senses it's presence, and after a delay to make certain the source is "stable"... it transfers the load back to the utility's lines, and shuts down the emergency generator's engine, in preparation for any future power loss. You don't have to do a thing. It's totally automatic. No more spoiled food or flooded basement because the sump pump didn't work! Plus, it works the same whether you're home or not. So if this natural disaster happens while your visiting family in a different state, or country, the generator and ATS will take care of everything for you.
Engines of the today's residential emergency generators are mostly "dual fuel" rated. Meaning they will run on either Natural Gas or Propane (LP - Liquefied Petroleum). Most manufacturers offer a diesel engine on some of the larger models but they are much more expensive and not available on as many models and sizes. Fortunately for us, and you, Kohler's line of Residential Emergency Generators is available through 150 KW in a gaseous configuration. In the realm of Residential Emergency Generators, the power output range is between 6 KW and 150 KW. Larger than that puts us into Industrial Generators which we cover in a separate topic.
Classes of Emergency Generators
Electric power generators can be classified in one of three ways depending on their mode of operation: continuous, prime, or standby. Continuous and prime generators are primarily used in remote locations such as your "Summer Cabin in the Mountains", or "That Deserted Island Paradise" after retirement. In rare cases, it may also be cheaper to generate power through a diesel generator than to buy electric power from the grid. So we need to discuss your application in a little more detail to establish which way to go.
In reality, most residential emergency generators that we sell and install are used as "Standby" or "Backup" units. This term means that your dwelling's "primary" source of electricity is something other than the generator, i.e. utility power from some power company. When that power is lost, the emergency generator kicks on and your back in business. But the majority of the Residential Emergency Generators are NOT meant to be run "continuously". And in fact, doing so may void the manufacturer's warranty. Running these units continually and/or for a long time due to environmental needs, will cause them to overheat, and the engines will most likely use oil. Make sure you check with your sales rep if you think you've got an issue, BEFORE you buy the generator.
The other scenario, is when the generator is used as "Continuous" or "Primary" power! Some folks want to "live off the grid", and in such a case, if your primary source for electricity is going to be an Emergency Generator, make certain it is DESIGNED and BUILT for "Prime", "Continuous" or "Off-Grid" service. Generators used for "Prime" power need additional cooling that usually isn't part of the package of the "Standby Emergency Generator". In most cases this means the "Prime" generator engine (and maybe the alternator itself) will be "water cooled". Very much like your vehicle. Additionally, engine air cleaners and the lubrication system need to be more "robust". Many generators for "Prime" service operate at a much slower RPM than "Standby" units. Standby systems may operate at 3600 RPM or 1800 RPM, while it is possible that a "Prime" generator will be designed to, and operate at, 1800 RPM, 1200 RPM or even 900 RPM. The slower the better for extending the life of the engine. In short... the generator used for "Prime" service has to be tougher and "made for the job". Make certain your new generator has those extra features if you're using it as "Primary" power. We can help you make that determination.
Sound Levels a Concern
One factor that potential generator customers always ask about is the "sound level". Let's be honest here, a generator is going to make noise! How much and at what level is the real question. Manufacturers today do their utmost to reduce the amount of "objectionable" sound that is produced by the generating system. They use sound deadening insulation on the enclosures, as well as actually changing the airflow and design of the enclosure itself to reduce noise. But there is still going to be "noise". Sounds from a generator happen due to various factors, such as the size of the engine, the exhaust, and the overall vibration of the unit.
A generator’s noise varies depending on the size of the engine and its load. Sometimes this is going to vary depending on the model of the generator. More power output will always result in a louder generator. For example, a 10 KW generator will be louder than a 5 KW generator. And, the decibel level will also "always" change according to the load requirements from the generator. Apart from the size of a generator, the noise produced by the engine depends on many factors. For instance, ambient surroundings can affect the sound rating produced by two identical gen-sets. In addition, the exhaust is a major contributor to the overall noise level of a generator. And the cooling fans, which apart from cooling the system, are also responsible for altering the sound level of a generator during operation. The sound of a cooling fan varies depending on the operating speed and the fan blades design.
But manufacturers work hard to reduce these sound levels by modifying those components contributing to the sounds. Exhaust systems are modified, AND, some manufacturers even offer different exhaust mufflers that reduce the sound even further. Rubber or spring dampers are used to cut the sound contributed by engine/generator vibrations and fan blades are tweaked to produce enough cooling air for the system, yet minimize air noise. But a critical component is the enclosure and how it is insulated. Manufacturers offer different "sound attenuated" enclosures to minimize external sound levels as much as possible. And all of this works. But we understand too, that your generator is going to be located in a "residential" neighborhood, and you want it to be as unobtrusive as possible.
So let's look at sound levels for a minute. Here are some common "sounds" from everyday living.
- Normal breathing - 10 DBA; Whispering at 5 feet - 20 DBA; Soft whisper - 30 DBA
- Rainfall - 50 DBA; Normal conversation - 60 DBA; Air conditioner - 60 - 75 DBA
- Vacuum cleaner - 60 - 85 DBA; Flush toilet - 75 - 85 DBA; Baby crying - 110 DBA
And now some Kohler Emergency Generator sound levels:
- 12 KW - 71 DBA; 20 KW - 69 DBA; 38 KW - 62 DBA; 60 KW - 61 DBA; 100 KW - 71 DBA
- 150 KW - 73 DBA
So you see, with the attention spent by a reputable manufacturer to minimize objectionable sound (noise), their generators, while running under full load, are quieter than "flushing your toilet".
A transfer switch is an electrical switch that transfers electrical power between two sources. In our case, an automatic transfer switch (ATS) is installed between your home main electrical panel and the emergency standby generator. This transfer switch allows you to have your Residential Emergency Generator provide power to the circuits you want to power in the event of a power outage. Compared to a "portable emergency generator", with a transfer switch installed, you eliminate the need for running extension cords to each individual appliance which makes for a safe, up to code installation.
For home applications, there are two types that we will look at, the manual and the automatic transfer switch.
A manual transfer switch allows you to manually switch the power source from grid to generator with the flip of a switch. The manual transfer switch is a 2-position switch. One position closes the contacts between the load and the "normal" or "utility" power, and the second position closes the contacts between the load and the "emergency" power. It is NOT possible to have both positions energized at the same time. These switches are much less expensive than automatic transfer switches but will require you to access your switch during the event of a power outage. They also allow you to manually manage the amount of load on your generator to prevent overloads. Features to consider on the Manual Transfer Switch:
- Inexpensive - Manual switches are less expensive than their ATS counterparts.
- Easy To Control Loads - With switches on each circuit, you can control the load that your generator is under to prevent overloading.
- Easier To Setup - With less moving parts and no programming needed, a manual switch is much easier to install
- Requires Manual Switch Changeover - In the event of a blackout, you will be required to manually flip the switch to allow your generator to power your home. That means you have to physically be home!
Now the Automatic Transfer Switch (ATS). An automatic transfer switch allows you to automatically switch the power source from grid to generator as soon as you lose power. These switches can be programmable to automatically power the highest priority circuits during a black out. With convenience comes cost, and these automatic transfer switches are no exception. With more features & higher maximum watt ratings, automatic transfer switches are generally priced higher than manual transfer switches. Let's consider the Pros and Cons of the ATS:
- Easy To Use - When there is a power outage, the ATS automatically switches power, no manual switching required.
- Programmable - Some ATS units are programmable to be able to put a higher priority on more important appliances to prevent overloading.
- Expensive - Compared to manual switches, the ATS is considerably more expensive, however, you get more features.
So you need to consider a couple of things when you're selecting your Emergency Standby System and the transfer switch... "Do you want it to be "Totally Automatic"", or "Are you going to plan on being home "when the lights go out""? Before you make your final decision, get a price comparison from our sales team. You may find that the cost for the Safety, Convenience and Automatic operation of an ATS isn't that much more than the manual alternative.
Installation and Startup
A.R.&E. is not in the business of performing the installation of your residential emergency generator systems. We have partnered with numerous electrical and mechanical contractors within our Quad-State marketing area, as well as a significant number of LP Gas suppliers. We can work with one of these companies or we'll work with YOUR contactors to assure a successful installation of your Residential Emergency System.
There are a couple of different methods to perform an installation depending on YOUR needs and requests, as well as methods REQUIRED by local and national codes. And believe me, local codes are certainly different.
If you have selected a "Whole House" system, the installation will include a full Automatic Transfer Switch that is rated as a "Main Service Entrance Panel". This will basically replace the main electrical panel in your home, OR it will be installed between the power company's electrical meter and your MAIN electrical panel.
If you have selected a "less than Whole House system", the ATS will be mounted somewhere near your main electrical panel. A NEW branch circuit breaker will be mounted within your main electrical panel, of a rating large enough to handle the loads that you've requested. This new branch breaker will be wired to the POWER LINE side of the ATS. A NEW "Emergency Circuits" panel will be supplied and wired to the OUTPUT terminals of the ATS. We will then physically "move" the circuits you've selected to be energized during a "power outage", from your main electrical panel and place those circuits in this NEW "Emergency Circuits" panel. Because this NEW "Emergency Circuits" panel is connected to the OUTPUT terminals of the ATS, the circuits that were moved, will be fed during both the "Normal" operation of the system, and the "Emergency" operation, after the ATS has transferred to the generator.
Once all electrical circuits have been re-wired and the installation inspected and approved by the local inspectors, we're ready to test the system. During this process the installation by your selected fuel supplier of the fuel to the generator will have been coordinated, and that too will have been inspected and approved by the regulating authority. A run test will be performed, and with your permission, we will disconnect utility power to your home to provide a "TRUE" power loss test. We'll do a walk-through with you to verify that all circuits are energized that you requested, and instruct you (and your family) as to the operation of the complete system and what to expect. We'll go over the maintenance of the engine and answer any questions concerning the complete project and it's culmination. We'll also go over our "Maintenance Program" with you, should you feel you'd like our technicians to perform the required and routine maintenance to keep you generator running at peak efficiency and power.
The installation is complete and you're ready for your "first power outage".
Application and Selection Process
This is the final step in this topic about Residential Emergency Generators. And one of the most important things for you to know is that "you aren't doing this alone"! Our Application Representative will come to your home and do a "walk-through" with you. We'll record the number of items you want to control with the generator and their various "electrical wattage rating". We'll look over the property with you and listen to your requests for the location of the generator and any external fuel tanks or other accessories that might be needed for the system. We'll return to the office, make the appropriate calculations, contact the factory for product availability (if it's not in our inventory), and prepare a quotation for your use. During this process, we may need to have an installing electrician with us to assist in the determination of specific code requirements in your particular jurisdiction. This is assuming your project is a "retrofit" at an existing home. If it's a completely NEW home, either under construction or still being dreamt about, we'll sit with you and your architect, engineer, electrician, and/or contractor to obtain the required information.
When it's all finished and you have your quotation, we'll be here to answer any questions that have not been sufficiently addressed and ease your mind about any uncertainties. We're here to help.