What is A Power Generator?
A generator provides an independent source of electrical power to operate your electrical systems. You might use a power generator when your normal power supplies fail.
If you have solar panels that are grid tied, for safety reasons they will not be permitted to provide your home's power when the grid goes down, unless you have installed specialised isolation switching. That needs to be installed to permits your solar power system or engine driven generator to be used to provide standby power to the home when the grid is down and until normal power resumes.
Standby power may come from a motorised electricity generator, an uninterruptible battery power supply or from solar battery equipment.
Time Out For Grid Failure
The period of your outage can vary depending on the cause of the failure. Mains grid power can fail when power lines are damaged in vehicle accidents or from bushfires. It might be a problem in another area or at the switchyard that needs your area of the grid to be electrically isolated from the network.
The cause might be power lines have collapsed during inclement weather isolating an entire area or be more localised if they were brought down from a vehicle impact. A substation may function to prevent a failure of the whole power grid by isolating affected areas. In other words, your mains electrical power may be cut for an undetermined period of time.
A portable fuel driven (propane, LNG, diesel or petrol) engine back-up generator could provide local emergency power after a natural disaster or a human caused one.
Power generators can be used in homes, offices, factories, commercial centres and recreational vehicles in a variety of applications and circumstances. Back-up power generation systems reduce the financial and health consequences during an emergency situation with loss of electric power.
The emergency backup generators for major commercial and medical centres are standby generators that are usually driven by reticulated natural gas, bulk propane gas or diesel. The smaller portable home backup power system may use a propane gas bottle or petrol tank to operate an electric generator's engine. To operate the back-up generator safely on the home circuits, the failed electrical grid connected to the home must be isolated from the home at the power meter.
More recently UPS style battery systems and solar power generators backed with batteries are being used for standby power. These battery style backup systems are automatically switched and have the advantage that they do not produce noise or polluting exhaust gases. That means the backup electrical UPS/ battery bank can be placed within the security of the main building.
Power Generator - When Is One Used?
A standby generator may be a feature in the fixed infrastructure of your home if you live within the area of an irregular power supply. Countries with developing power infrastructure tend to have intermittent interruptions to electrical main power. People who don't want to be affected by this regular power interruption get back up power systems connected into their switchboards. These generators will provide added support to the solar PV system during grid failures.
A power generator could be an add on feature for a home with a hybrid off grid system where a solar photovoltaic panel array and battery support an off-grid power system, are additionally supported by a standby power supply when it's needed.
Regular engine driven standby generators are installed away from the main household, usually in a sound insulated building having good ventilation and exhaust fume removal.
A sensor on the grid side of the building’s electrical system detects the power dropout. When mains power is lost a transfer switch activates the battery to start the generator when the generator is needed. There may be a
This automatic transfer switch simultaneously disconnects the mains grid, starts the generator and connects emergency power to designated circuits. One side of the transfer switch is connected to both the normal power feed and the emergency power feed. The other side of the transfer switch is connected to the electrical circuits with the load designated as emergency.
While the generator or battery backup is operating electricity is live, so all circuits remain isolated from the network’s grid. After the generator starts, only the designated emergency circuits in the building are powered up.
Power Generator For Home Standby Use
More householders are keeping a portable backup generator around just in case they are needed. It might be helpful for rare occasions where some backup generator power is needed for keeping fridges and lights operating.
Household standby generators tend to be larger fixed power units that are often tied directly into the natural gas lines. In areas without reticulated natural gas they can be tied to bulk bottled propane gas.
Standby generators are designed to fire up immediately when the main grid power drops out. They fire up within seconds, so main grid power outages will not mean food spoils, or remove cooking and security lighting options. The standby generator needs to be wired into the house meter through an automatic transfer switch and grid adhering to strict safety regulations.
Standby generators have also become popular in US communities where people live with a strong likelihood of damaging storms, bushfires or where a poor end of line service is subject to frequent intermittent power drop-outs. A consequence of such power outages might be using candles for few nights with the food spoiling in your fridge.
Losing power will normally mean the loss of home air conditioning or heating. Consequently, the environment in severe climates might become uncomfortable without power. Though for very young children and older people it may become life threatening for them during periods when they are ill.
Appropriate standby generators represent a significant investment for those who need one to survive regular power outages.
What Generator Wattage Do I Need?
Before making this purchase write down which appliances and devices you consider essential to be using in your home. Work out the amount of energy those powered items need to keep them operating. Your standby power system will need to generate at least that amount of power to run.
Electric motors in appliances like washing machines and fridges would normally use more power than static electronic appliances like televisions. Remember also that when electric motors start they require a larger short burst of power. Without mains power, the generator or batteries will need to provide that surge of starting power. Your room heating or air-cooling systems, your refrigerator and freezer will probably need a chunk of that power allocation.
Not everything will need to be operated on standby power. For a lot of people it’s unnecessary to power every appliance in the home with a standby generator. Some things can be left switched off until mains power is reconnected.
You’ll want to compare that wattage needed for running the household appliances with the wattage measurement given with the generator. You shouldn’t simply match the maximum household wattage needed with the maximum for the generator.
The generator could feasibly operate at that maximum level for short periods. However, the standby generator is likely to fail if it’s run continuously at the maximum listed kilowatt capacity.
What Fuel Source For Your Power Generator?
There are options available for fuelling a generator fixed at a location. Natural gas is a good option for locations where reticulated gas supplies are available because those supplies are rarely interrupted.
Natural gas is an appropriate fuel for a power generator. Connecting the generator to natural gas is initially more expensive but there is peace of mind knowing that you won’t run out of fuel when the connection work’s completed.
A gas plumber will safely connect your gas line to the generator. An electrician must connect it to the grid, the emergency power circuits, your generator and it’s transfer switching between the grid into the house electrical.
Transporting fuel (gas, diesel, petrol) to a standby generator when a storm is passing through your area is inappropriate. Fuel station pumps may not operate due to being affected by the outage and it is possible that roads between your home and the fuel station may be impassible at the time you need that generator fuel.
Propane is a good off-grid generator fuel solution when natural gas is not available. Bottled propane fuel is more expensive than natural gas and bottled gas could become a fire hazard in some situations.
Propane needs to be appropriately stored and accommodated. When a power shut off occurs you need sufficient bottled propane supplies for the duration of the standby generator operation.
Power Generator Features For A Home System
You buy a power generator for emergencies but some people might ask how would they get the best value from their power generator purchase when the power stays on? You won't be saving money by buying something that looks practical but doesn’t work when required in emergencies. You need to check and do maintenance on the generator from time to time.
Keep in mind that there are a number of different factors beyond the generating capacity of the unit when it comes time to pick your power generator.
Power Generator And Electronic Equipment
Computers, communication equipment and some other sensitive electronic devices are vulnerable during blackouts and power fades. These bits of equipment need a steady flow of electrical power to operate. When voltage drops appreciably, or drops out totally, these sensitive electronic devices may fail to operate or switch off. That can occur even during the time a backup generator uses a minuscule time interval to start-up. The small gap of time without power continuity means power surge protection strategies are needed. To prevent your sensitive equipment’s damage, connect them to the grid and emergency power through an uninterruptible power supply circuit. (The UPS is connected to the emergency circuit.)
The UPS will directly feed the sensitive electronic equipment by being connected to the designated emergency circuit’s outlets. Select a UPS that can feed and can power the required number of circuits and household devices.
Portable Generators For Camping
Portable generators are useful for power outages and for projects requiring power tools at a remote site, and excellent for camping. The right portable generator can turn camping into glamping.
If you are considering a camping trip it doesn't need to be a 'rough-it' experience. Glamour camping is mixing the outdoors with luxury. With a portable generator your campsite always has a power outlet to run a coffee maker, an electric stove, a fridge, a microwave, your inside and outside lights, fans, computer and to charge the electrical gadgets that keep the kids amused when they are awake and you don't want to go swimming, biking, fishing or walking again. You can run these appliances, but obviously, not all at the same time.
Camping generators are useful in remote locations away from mains power. There are things to consider when choosing a camping generator, including:
Size & Weight
The generator is going to be a part of your camping equipment, so along with the portable fridge, tent, stove, water & food, bedding and clothes there is a lot of stuff to load into the vehicle to get there and again to return home. Choose a generator that will be powerful enough to do the job but remember that a smaller sized generator is going to be lighter and will be easier to load, stow and to move around.
Quality Of Power Output
The inverter generator is recommended because it has better ‘quality’ of power output with a good voltage control system, so they won’t damage your appliances. Inverters create sine wave power with accurate voltage levels that are ideal for sensitive electronics like computers. Inverter generators are quieter, lighter and with good fuel efficiency.
The quieter the generator the better is your camping experience, so a good quality muffler should ensure that its decibel level for your recreational site maintains a relaxed layback atmosphere for a restful break. As a guide, you want less than 60 dB as a quiet generator for camping. Decibels are explained below.
Fuel Efficiency & Endurance
A fuel-efficient generator with a reasonable sized fuel tank capacity will provide good endurance. Inverter generator engines adjust their engine speed to match the load demand, which ensures better fuel efficiency.
Service and Technical Support
When camping your power generator is usually the only power source you have, so if the generator stops working you might need to go home early. That means you need to do maintenance and "look after the unit".
Make sure the camping generator you choose has good locally based after sales support that can look after any warranty and service issues that may arise. The better brands usually have fewer breakdown problems but when they do fail the warranty ensures first-rate back up with genuine parts and service to get you back in the field.
Look at the period of warranties provided and check whether servicing centres exist in your local area. Read the warranty provided to see what it covers and what it doesn’t cover. Usually good quality is more likely if you purchase a better brand name generator. It’s a bit more expensive but it is less likely to fail, however, if it does stop working the good brand name generator you buy usually has a straightforward warranty and a longer warranty period.
The louder the sound the more amplitude the sound wave has. Also, you might recognise that distance inversely affects the intensity of sound. The greater the distance from a source of noise the quieter a recorded sound at the point of measurement. You may have noticed that many recorded sound levels for generators are cited at a decibel level for 7 meters from the source.
The decibel measure is on a logarithmic scale for describing a ratio of power, sound pressure and voltage. Sound energy travels in waves that are measured using its frequency and amplitude. Frequency in Hertz (Hz), measures the number of sound vibrations per second. Amplitude is reported in the decibel (dB) scale and measures the sound pressure level or the intensity of a sound at your ear or the measuring instrument.
The logarithmic decibel scale measures sound differently than a linear scale would. For example, every increase of 10 dB on the decibel scale is equal to a 10-times increase in sound pressure level (SPL).
Near to total silence is 0 dB. A sound 10 times more powerful is 10 dB and 100 times more powerful than near total silence is 20 dB. A sound 1,000 times more powerful than near to total silence is 30 dB and so on.
- Near silence - 0 dB
- Normal conversation - 60 dB
- Freeway traffic – 85 dB
- An operating two stroke engine lawnmower - 90 dB
- A police siren - 110 dB
- A jet engine - 120 dB
- A shotgun blast - 150 dB
Portable Generator Safety
Never run a portable generator inside a confined habitable space, like a room or in a tent. The fumes from generators are toxic and poisonous. Always look after your portable generator and maintain it regularly if you need it to continue being of service.
Here are some safety suggestions worth emphasising:
- Maintain a minimum of five feet of clear space around your running generator.
- Only operate the generator outdoors. A carbon monoxide build up in an enclosed space is lethal.
- Never refuel the portable generator when it’s hot. Spilled fuel can ignite on a hot surface and can seriously burn you or ignite the ground.
- Never fill the fuel tank to the top or fill fuel carrying containers to the top - you need to leave room for expansion.
- Let your generator completely cool down before stowing it.
- If you want a connection from the portable generator into your home, have a properly qualified professional electrician install a transfer switch in the house meter-box and connect it there. It will save multiple power cords from the generator to appliances being damaged.
- Ensure your generator is properly grounded, so you don’t risk electrocution.
- Overworking your portable generator will cause it to have the breakers overload and cut power.
Portable Generator Load
A portable generator offers you (back up) electricity until the normal power supply is restored or until you get to somewhere there is mains power available. The small size camping generator can run just a few basic necessities for recreational use. Below are the power draws of a few common items for an idea of what your generator can run. You can add the wattage of electrical gadgets you own to have some idea of the wattage demand that will be drawn from the generator.
- Incandescent lamps use 60 to 120 watts.
- A sump pump uses 750 to 1,500 watts.
- A refrigerator uses 500 to 750 watts.
- Computers use 60 to 300 watts.
- Heaters use 500 to 1,500 watts.
- A coffee machine uses 750 to 1,000 watts.
- Halogen work lights use 300 to 600 watts.
- An electric drill uses 500 to 900 watts.
Remember that when you are looking at power consumption, many electric devices can draw higher demand when starting, and that surge can be between 2 and 3 times their usual operating demand. That surge can be a one second up to ten second pull when you start your electrical gadgets but you can spread this load if you choose to start them one by one. That means you won't get one big surge and a breaker overload.
Types of Portable Generators
Portable inverter generators use a gasoline or propane fuelled motor that rotates a coil within an electric field, essentially changing the engine’s mechanical energy into electricity.
Inverter generators have automatic controls for power fluctuation, changing their power output. Those additional controls for inverter generators makes them relatively more expensive.
Portable Generator Efficiency
Portable generator manufacturers quote their run times in specification sheets, but most don’t quote for a generator running at full capacity. Instead, as you rarely run a generator at peak performance for very long, they will use a number of hours endurance at 50% output capacity or even 25% output.
You also have to consider the wattage you're consuming.
A portable generator running ten hours at 50% capacity, that is able to deliver 2000 watts at maximum, is not going to run 10 hours at 50% when the power you're needing is 2000 watts. You will need a bigger generator or lessen the load.
Fuel: Gasoline Or Liquid Propane
There are many portable generators that run using liquid propane but these models produce less power from an equivalent amount of gasoline. And the Propane fuel storage takes more space that gasoline does. So, comparing size, the fuel tank of a gas-powered unit is considerably smaller than a propane-powered unit running for the same period.
That means the space to store the propane is more and using standard propane bottles, you will need to change them over more regularly. Our preference is a gas-powered engine.
Portable Generator Features
After working out the size of generator for the power you need, consider the added features you want with a portable generator. Many of these features are generic for all generators.
Ease of Start
The pull start generator should have decompression for easier starting. The electric start option using a key or a button to start adds convenience and weight.
Ease for checking fuel levels with a float gauge or glass & plastic visual tube will save you taking the fuel cap off to see fuel levels.
Oil Level Warning
You will damage your equipment if the oil level drops too low to be effective. An oil warning light, or oil sight glass for sump level can prevent running the engine without oil.
A throttle sensor that can adjust output contingent on load input. This feature optimises fuel efficiency and run time.
Portable inverters don’t generally have wheels, but even a relatively light generator needs to be moved around the campsite. It can be easier to move a generator with a trolley so that you prevent back injuries during the lift and carry part of the move.
Multiple Power Outlets
Portable generators may have one or two 120V AC outlets and also a 12V DC outlet on the generator. Some may also have a specific RV 120/240V 30A outlet that you can plug directly into your RV's electrical circuit.
If you want to use a generator as a home power back up you will need to install a transfer switch on the meter box. A transfer switch allows you to plug your portable generator directly into your household with a single cable, instead of having a number of extension cords through doors or windows. A qualified professional electrician must install the transfer switch. Small portable generators are not designed to run a household load.
You can buy an engine driven power generator in sizes from small portable through to standby power for a large commercial business or factory. This article explains the features to look out for when buying a generator. The main issues for generators relate to convenience and safety. Buy a brand name that delivers a good product and can be found in your area so the machine can be serviced and should any problems arise with its performance, the warranty can be used if the warranty period is in time. We have done reviews of portable generators to help you when it comes time to make the purchase. We welcome comments in the box below. Please be free to share this article within your network.