What is watt and watt hour? 

When it comes to electricity, to better understand how we use it, it's crucial to know the difference between Watt (W) and Watt-hour (Wh). Let's firstly take a look at the definitions of the two units:

  • W=a unit of power, it is the amount of energy an item needs to function; the rate at which energy is consumed
  • Wh=a unit of energy, equivalent to one watt (1W) of power expended for one hour (1h) of time. It is the amount of energy an item consumes over a given timeframe; a way to measure the amount of work generated or performed.

Watt Hours are calculated using the equation: Watt Hour= Watts x Hours

Amount of LED Light electric energy usage

Household electricity consumption is the most common electricity usage in our daily life. 
Let's take LED light for example. Light bulbs are usually referred to by their wattage. A 10W LED light bulb when on will consume 10 watts of electricity. The average daily usage of bulb on is approximately 5.5 hours, so the light bulb would consume 55 watt-hours (5.5 hours X 10 watts) per day. That is the measure of the energy consumed to do the work of lighting up the light bulb.

The Usage of W and Wh in Power Generator

But when it comes to the power generator, what are the elements that relate to W and Wh?  
Let's take DELTA for example.
Here are the specifications of DELTA 

We could detect that for generator, W is  the unit used to measure the output power, Wh is the unit used to measure the capacity of a generator.

The capacity of DELTA 1300 is 1260 Wh while it supports AC output up to 1800W. 
The AC Output is 1800W, which means that DELTA could support any appliances whose rate of power is less than 1800W.

Here we list some appliances that DELTA can support:
(Surge below 3300W)