Whether you’re new to RVing or Tiny House living, or very experienced, we should talk about electricity.
First, you should know that there are two basic types of electrical current, AC and DC.
AC is short for Alternating Current; the outlets in your home are AC, and most of the things you plug into the wall run on AC power (most, but not all).
DC is the abbreviation for Direct Current; Your car battery supplies the systems in your car with DC power, the stuff you plug into the accessory outlet in the car run on DC power (again, most, but not all).
If you’re wondering why we bring this up, it’s because living in an RV or a Tiny House is most likely going to present you with using a mix of these two very incompatible forms of electric current. Understanding this is important to living safely and comfortably in a tiny space.
For the purposes of Tiny Space Living, we’ll keep our conversation simple, and centered on systems most relevant to RVs and Tiny Houses.
RV’s usually have a power interface, also called a “hook-up”, that allows you to plug directly into a grid-sourced power cable and supplies your RV with all the AC power you need while you’re parked in an RV camp ground. This allows you to use conventional small appliances in your RV.
The majority of RVs rely on using these ‘hook-ups’ to power their systems. The same kind of system can be installed in a Tiny House.
RVs also generally have a small back-up generator and battery bank for times when hook-ups are not available. The generator produces AC power, and can run household appliances directly while it’s running. It also charges the battery bank. The battery bank, like the generator, can also run your household appliances.
Here’s where it gets tricky: The generator produces AC power, but to charge the battery bank you’ll need DC power. The battery bank supplies DC power for use without the generator, but your household appliances need AC power to operate.
Fun, right? Electricity is vexing.
As luck would have it, this confusing situation has been worked out by brains bigger than my own. Two devices, the Inverter and the Converter, are used to change the current types so that our systems can integrate and seamlessly provide your tiny living space with electricity.
Let’s take a tour of what these three components, the generator, inverter, and converter do, to make life good.
First, Generators make electricity
Most small gasoline powered generators produce AC power, which is most useful from a consumer’s point of view.
The generator produces usable power only while it’s running and doesn’t store any energy for future use. You can plug directly in to most generators. Most folks put the generator where the noise won’t be bothersome, and run extension cords to where they need power. Some RVs have integrated generators in sound-dampening spaces.
Solar generation has a few more steps.
Solar panels generate power only when enough direct sunlight is hitting them. The DC current produced is then stored in a battery bank.
Because DC power needs to be consumed in very specific voltages, few devices can run directly off of a solar panel generating electricity without first running it through either an Inverter, or DC adapter.
Still with me? Good.
You can buy all the components for solar generation separately and assemble a system to accommodate your specific needs, or you can purchase a “Solar Generator” which also includes the battery bank and inverter, usually as an integrated unit.
Both types of power generators have obvious advantages and disadvantages. A long stretch of rainy days can leave your solar power running low, but an extended stay off the grid might leave you without fuel to run the gasoline powered generator.
Moreover, a good RV serves as a comfortable home outside of your actual home. You may fill it up with modern appliances or other comforts unique to you. In this case, the best RV generator is a great option that helps you to make your RV modern and functional. It is also necessary to consult some RV generator reviews to get a good camping generator.
See also: What Size Generator Do I Need for My RV?
Many use a combination of both, but either one will probably require the use of inverters and converters.
Let’s Talk About Inverters
An inverter takes DC electricity and changes it into AC electricity.
If you’re using solar panels or any kind of battery bank, the power coming off them is DC, which you’ll generally want to change to AC before it’s useful to you. You can’t plug the coffee maker into a car battery, it simply won’t work. An inverter takes DC power and changes it to AC power, allowing your fair-trade medium roast to fill the pot. You’re going to want that.
Seriously. Without an inverter you’re limited to DC power.
Inverters produce a number of differing types of Alternating Current; Square wave, Modified (Quasi) square wave, and True/Pure Sine wave. Each type being better or worse depending on your needs.
True/Pure Sine Wave
This is what you get straight out of your home outlets. Some generators are equipped to provide pure sine wave, but most inverters aren’t quite as clean as grid power sine waves. Practically everything you own with a plug will run as designed on a Pure Sine Wave inverter. It’s the ideal. If you’re going to run a computer, or any sensitive electronic equipment, you want this type of inverter. They’re the most expensive but will perform the best for all your needs.
Modified (Quasi) Sine Wave
A Modified Sine Wave inverter will work with most appliances, but it’s a less “clean” signal, which can impact the efficiency of some devices. As a result it can cause some appliances to draw as much as 20% more power. It’s not recommended for highly sensitive equipment, but will work just fine for motors, compressors, and household appliances. You may notice some reduced performance from light fixtures and multi-speed power tools, but it will run them. The majority of consumer grade generators use an inverter that produces a Modified Sine Wave. In most cases this is a solid choice.
If you find a super great deal on a generator it may have a Square Wave inverter in it. Check. If it does you should keep looking; it’s not as good of a deal as it may seem. Square Wave inverters will run simple tools, but little else. If you’re still using your Grandfathers Black & Decker corded drill, you’ll probably be ok, but not much more will work correctly. It’s a “dirty” wave, and it lacks enough frequency range to be very useful. Our advice is to avoid them.
A converter essentially does the opposite of what in inverter does: it changes AC power into DC power.
You might be wondering why anyone would want to do that. Many of todays electronics have batteries that charge on low voltage DC input. If you have any small electric appliance that uses a “DC adapter cord” chances are the adapter is converting the 120V AC power into a specific DC voltage.
Different devices use power differently, so not all adapters are interchangeable. Small converters are what allows these different adapters to accommodate the power needs of specific devices.
Another application for a converter is charging large battery banks from a conventional power source (AC). You’ll still need to convert the power to DC in order for the batteries to store the energy. Battery input must be a low voltage DC in order to charge. (Converters are also used in welders, but we’re hoping if you own a welder you knew this already.)
A converter can turn DC into AC like an inverter, but for the sake of keeping things simple and easy to understand, we don’t need to talk about that. Suffice to say those instances are an order of complication higher which would only confuse us even more at this point.
There are three common types of converters:
- An analog-to-digital converter (ADC)
- Digital-to-analog converter (DAC)
- Digital-to-digital converter (DDC)
Converters are now widely used in the electronic devices, power supplies or circuits requiring specific voltage and current levels.
Inverter vs Converter
In comparison with inverters, converters are usually mentioned. Both are electrical devices that convert current but do different functions. The following table is the comparison between them:
|Definition||Electrical devices convert the voltage from DC to AC.||Electrical devices convert the voltage from AC to DC.|
|Functions||Convert DC electricity from solar panels, batteries or fuel cells to AC.
Convert DC power from solar panels to AC for the electric grid with micro-inverters.
Supply AC power if main power is not available in UPS or uninterrupted power service.
Used for induction heating.
|Convert AC to DC.
Detect amplitude modulated radio signals.
Supply polarized voltage for welding.
|Drawbacks||Not perfect for inductive AC and motor loads.
Sensitive electronic devices can be destroyed by poor waveforms by low batteries.
Need a good source of power for re-charging.
|Poor current overload capacity.
Good quality Automatic regulators are more expensive than Mechanical ones.
The Difference Between Inverter vs Generator
It is essential to know the difference between inverter and converter, especially where you want to change or convert power from one energy form to another.
The table below will summarize some of their common differences:
|Functions||Draw power from a fixed DC source and use electronic circuitry to invert DC to AC.||Produce electrical power|
|Time and effort to start||Take no time gap in the onset of power.
Start on their own, once power is gone.
|Take considerable time.
Take the effort to start.
|Fuel||Use stored DC electrical energy in a battery (or a battery bank). Require not much maintenance||Use fossil fuels (diesel, propane, gasoline) as the main power source to run an engine. Require periodic maintenance|
|Noise||Be virtually silent.||Be noisy.|
|Capacities||Are available in lower capacities.||Be available in high capacities.|
|Requirements||Require installation and wiring.||Can be started right out of the box.|
|Availability in places with power cuts||Be more convenient in places with short power cuts.||Be more advantageous in places with long power cuts|
Some Thoughts on Installation
- Inverters, like all electric system components, should be installed in accessible and reasonably flat areas that are rather clean, out of direct sunlight, away from fire and smoke, and have suitable ventilation.
- Always keep the inverter dry. It is very important to protect its space from rain or moisture.
- The leads of an inverter have an appropriate size and must be kept to a minimum practical length to avoid voltage drop and overheating.
- The inverter should be placed as near as safely possible to the power bank (battery packs), but NOT in the battery or engine compartment.
- For the best performance, other surfaces or objects should be at least 250 mm far away from the ventilation openings.
- Place the inverter carefully and check it often to avoid the insects that nest in the heat dissipation vents. Spiders are especially attracted to the heat of electric components.
- Routinely maintain the inverter and its battery. Replace if the battery is damaged and not combine old and new ones in a system.
- The generator should be installed in a separate room or enclosure. In the event that it must be located in the same room as the rest of the system, put it far away from other components and cover its exterior.
- Allow ample space around the generator.
- If the generator is automatically started by other equipment, it must carry suitable signs and the auto-start system must include an isolator to disable it during repairs or maintenance.
- Take sound reducing measures in any way possible. Generator noise can ruin your own peace as well as your neighbors’ . In many places excessive generator noise is illegal.
- Generator fuel is dangerous. It must be kept in an appropriate container in a safe location.
Power systems can get a bit confusing. The deeper you dig into electricity the weirder it gets, but that’s okay.
Keeping things simple, here are the important things to remember:
- Generators produce power.
- Inverters and converters make the power from generators usable.
- Not all inverters provide the same quality of AC power, and not all converters will work in every application.
- Not all electronic devices use the same kind of power.
- Rvs and Tiny Houses will probably need both AC and DC power sources.
- The type of electronic devices you’ll use is important to consider before you set up an electrical system in your Tiny house or RV.
- Always hire a competent electrician if you’re not confident doing the work yourself.
We hope you’ve found this information useful. In the future we’ll dig a little deeper into setting up electrical systems in your tiny living space, and discuss tips and tricks from those who’re experienced.
And remember, while many of us tend to be do-it-yourselfers, electricity is an area where qualified assistance could save you from exposing yourself to serious risk.