Russell McMahon wrote:

> I purchased a 700 watt nominal petro genset recently for $NZ99 
> Say unit would run for 1000 hours with no maintenance.
> $99/$1000 = $0.10/hour.
> Assume 750 watt electrical and 80% efficient overall and 10 kWh/litre 
> for petrol and $1.40/l and 15% of output is electrical.
> Output = 0.75/.15 = 5 kW (750 W elec, 4250 W heat).
> Energy in is 5 kW/0.8 = 5.25 kW.
> Fuel/hr = 5.25/10 = 0.525 l
> Fuel cost/hr = .525 x $1.40 =~ $0.75

So far I follow you...

> If we throw unit away at 1000 hrs cost per hour is $0.85/hr = 
> $0.17/unit
> 
> That's about the cost of electricity per unit now 

Russell, what is "unit" in this context? I thought it meant a unit of the
generator, but then the numbers don't make sense to me. What does a cost
per unit ($0.17/unit) mean?

Calculating the cost of electricity according to your numbers, I get:
TCO (based on 1000 h): 850 NZD
Electric energy produced: 750 kWh
TCO per electric energy produced: 850 NZD/750 kWh = 1.13 NZD/kWh

Gerhard

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist