100 percent efficiency.
Here is a perfect example of e = mc^2 (famous einstein equation).
In this case, if you have 10kg of anti matter:
e = 10*(300 000 000^2)
kg*(m^2)/(s^2) = joules
So you'd have 9.0 Ã?? 10^17 joules
or 900 000 000 000 000 000 joules
Almost enough to power the usa for an entire year.
According to wiki:
In 2008, total worldwide energy consumption was 474 exajoules (474Ã??10^18 J)"
So if we wanted enough anti matter to power the world for a year:
(474Ã??10^18)/(c^2) = m
You'd need 5.2 metric tons of anti matter.
Basically you'd take trillions and trillions of tons of crude oil, and turn it into one truck containing 5.2 tons of anti matter.
THAT would be enough to power the world for an entire year. Just one truck's worth.
If you could find a way to safely impliment it into aircraft, vehicles, etc...you'd have incredibly efficient and powerful vehicles.
Basically, if we can harness anti matter, we will have 100 percent efficient everything.
A car is only 10 percent efficient.
You fill your car with 40kg of gas, and gas has an energy density of 45 000 000 joules per kilogram.
That means your car now contains 1 800 000 000 joules of energy.
With that much gas, you can go about 700 km. Only 10 percent of that energy is used to actually used to propel the car.
Now replace your car's engine with an anti-matter engine:
To have the equivalent amount of energy, you'd only need 2.0 Ã?? 10^(-8) kg of antimatter, or 0.00000002 kg.
Equivalent to 0.00002 grams of anti matter. It would also be more efficient, meaning you could go further.
Mind you, the huge problem with anti matter is that if comes into contact with ANY matter, meaning let out into the air, it would all immediately turn into energy, destroying matter in the process. This creates a perfect vaccuum.
So with 0.00002 grams, and a small leak due to an accident or whatever, you'd have an explosion equivalent to a full tank of gas.
The biggest bomb created by man is the hydrogen bomb (Tsar Bomb).
It released 50 megatonnes of energy.
It would only take 2.33 kg of anti matter to equal that.
The difference however, is that anti matter annihilates matter.
So where as a nuke or hydrogen bomb would displace the air, anti matter would complete destroy it. Depending on what anti-matter is colliding with, will dictate how big the blast is. This is a problem because if the blast size is large enough, (say, in contact with air, where the molecules are spaced out), you'd have a huge vacuum. Now you'd have air in the immediate vicinity rushing in to fill that void, and then the air behind that, and that, and that, etc...so basically the air in the entire world would move (in theory). As you move outwards from the blast, (so a bigger sphere), more and more air would move in to fill that void. Would probably completely fuck the weather.
Since anti matter does not let off anything (or else that would be touching matter and explode), it is theoretically impossible to detect.
The only way to contain it is within an electromagnetic field (hovering between magnets), in a vacuum.
Fortunately it is very difficult to produce.
It is the double edged sword of God.
Harnessed, it will bring us unfathomable power. All of our energy demands would be met.
Released, it would literally destroy the world.