Diesel fuel vs Electricity for heating

When discussing heating the general method is to convert all units to BTUs for comparison. Lately some convert everything to Watts.

Randomly snagged off the web:

But part of the comparison will have to include conversion method, how you extract or use the energy, because none of them are 100% efficient.

Rule of thumb in food equipment is 1000 BTU per Cubic Foot, but they are often mixing gases and can be much lower, worst case around 900 BTU/F3. If checking for a specific job, may want to talk to the gas supplier to keep from having a nice suprise.(or not so nice) -- JHF

Thanks for your concern,

I have seen these and other tables, I have researched them, made the conversions, and calculated what I believe to be correct, impurities in the diesel fuel aside.

My question to the forum was: "Are my calculations correct"

Looking around in some tables:

Light fuel lower caloric value = 42.3 MJ/kg (41 .... 42.8)

Light fuel density = 0.87 kg/litre (0.855 ... .93)

1MJ = .2777778 KWH

So in 1 litre = 42.3 (MJ/kg) * 0.87 (kg/litre) * 0.27778 (KWH/MJ) = 10.22 KWH/litre

==> 0.46 litre than becomes .047 KWH. 12% different from what you found.

But: 1. not certain we are talking about the same fuel, 2. maybe you took the upper caloric value (5% difference)

Also:

10.22KWH is the the energy the is generated when you burn one litre of light fuel.

But there is the efficiency of the furnace.

I found some figures of 70 to 80% for a traditional boiler in some publications, but the same article was talking of 107% for a high efficiency gasboiler. So how serious are they.....

We produce industrial gasfired infrared systems for drying paper, and when we count with 60% efficiency, 65 when we pull some tricks.

Good luck.

Thanks for your answer,

I was told to take into account that I can get 10,000 kilo calories per liter from the fuel we use here, but I hadn't thought to verify whether he was taking efficiency into account.

I shall get back to him on that.

For Heating purpose Disel heating is by Indirect method. while electricity can be direct. eg.

1.For space heating you can not use Disel oil directly

2.For Furnace/oven heating Disel is indirect while Electric heaters can be imersion type

So as an user you got know first what is the efficiency of the overall system eg Flue gas temprature,Radiation loss,Convection and conduction loss etc before concluding which one is cheaper for the particular appliaction based on current prices of both.

The efficiencies are easily calculated since the systems are new and well documented.

What want to know is the accuracy of my calculation based on 10000 Kilocalories per liter diesal fuel.

Thanks

Wait a minute guys. THe QUESTION lacks important boundary conditions. EXACTLY what comparison is being considered? Is the question 'residential space heating' or 'shaft work', or transportation?

Liquid petroleum fuels average some 18-20,000 BTU/lb. lower heating value (combustion products as vapor). One can 1) burn the fuel in the air to be heated (open flame), 2) burn the fuel in indirect combustion (typical home heating unit), 3) Burn the fuel in an internal combustion engine driving an electrical alternator feeding resistance heating coils, 4) Burn the fuel in an internal combustion engine driving an alternator feeding resistance heating coils AND capture the exhaust and cooling system heat for heating air.

The devil is in the details--of which we have none.

Hi Keith,

Thanks for your comment.

I had stated that I am working on a statistic given to me by the system engineer. He claims that I get 10,000 Kilocalories from a liter of diesal fuel in our country. After this, I calculate the efficiencies based on the specific equipment I am using.

So my question is still as it was: Is 0.0046 litres of diesel fuel (heating oil) equivalent to 0.0535 kwh of electricity based on the given value of 10K kilocalories produced by a liter of diesel fuel?

To quell your curiousity. My application is residential. I have water heaters equipped with both electrical heating elements and heat exchangers from a diesel burning water heater. I have designed an application whereby the smart house (EIB standard) calculates the cost of heating water based on the current price of a kwh based on the TOU pricing and based on the last purchased price of the diesel fuel.

Yes, your calculation is ok, based on 10,000 kilocalories per liter.

You can verify this for yourself just by typing ".0046 x 10000 kilocalories in kWh" into the Google search line. The answer comes back: 0.0534622222 kWh.