Gassss (LPG x Natural Gas)

[Nick_Burman]

One for the chemists here... I live in Italy and so far my house has been heated using LPG, which we also use for cooking. However, over the last 3 weeks or so Italgas (the national gas pipeline administrator) has been working to lay natural gas pipes in our street. This has led to the discussion about how convenient or not the switch to natural gas would be. Normally we go through 900 liters of LPG per year, however to see if it is worth or not I would need the natural gas equivalent in cubic meters of this same volume. However, the information I found on the internet is confusing (OK, Italian internet is crap, all ads and little content), leading to estimates ranging from a saving of circa 100 to 200 Euros/year to absolutely outrageous values. Obviuosly I'm making mistakes during conversion but so far I havent been able to find a proper relation between LPG and CNG. Could anyone please help?

 

 

Cheers NB

[MJI]

Remember that every gas appliance will need natural gas jets and also you cannot use natural gas in your car.

[Danemouth]

Also Natural Gas has a different calorific value to LPG which means that you will not use the same quantity of LPG as Natural Gas.

 

As MJI said your appliances would need to be converted to NG.

 

In the UK including taxes etc. but excluding conversion costs NG is definitely cheaper.

 

Are the Italian Gas people offering some sort of conversion process?

 

Dave

[Martin]

LPG (a mix of propane & butane) is around 14kWh/litre.

Natural gas (mostly methane) is around 10.5kWh/cubic metre.

According to the numbers I found on the internet.  Hope that helps

 

     Martin

[Jeremy Cumberland]

3 hours ago, Danemouth said:

Natural Gas has a different calorific value to LPG

There's precious little in it, in kJ/kg, but unless Nick can get a price for natural gas in terms of euros per megajoule or euros per kilowatt-hour, the conversion factor isn't easy to guess at. What pressure is used for domestic natural gas in Italy, for example?

 

Your 900 litres of LPG equates to 45,000 MJ per year or 12,500 kWh per year. Changing from LPG to natural gas isn't likely to alter this energy usage.

 

Check whether your boiler and cooker can be converted (and how much this would cost). The capital outlay could easily outweigh any savings.

[Nick_Burman]

17 hours ago, Danemouth said:

Are the Italian Gas people offering some sort of conversion process?

 

No, but it's not difficult. The heater will need to be seen by our plumber while I can handle our stove, it comes with nozzles for both LPG and natural gas which I can change myself.

 

 

Cheers NB

[Nick_Burman]

14 hours ago, Jeremy C said:

There's precious little in it, in kJ/kg, but unless Nick can get a price for natural gas in terms of euros per megajoule or euros per kilowatt-hour, the conversion factor isn't easy to guess at. What pressure is used for domestic natural gas in Italy, for example?

 

According to the page of one distributor, natural gas arrives at home at 0.02bar. I don't know about the UK, however here the natural gas market is open, so there are several distributors. The regulating agency in charge of controlling the market has a site where one can compare prices, which are all quoted per annum based on a series of factors including annual consumption. So, prices are quoted on a yearly basis.

 

Cheers Nicholas

 

[Nick_Burman]

17 hours ago, Martin said:

LPG (a mix of propane & butane) is around 14kWh/litre.

Natural gas (mostly methane) is around 10.5kWh/cubic metre.

According to the numbers I found on the internet.  Hope that helps

 

     Martin

 

I looked up the internet again and found a site which claims that 1L of LPG = 0.5kg of LPG = 5500kcal which would be equal to 0.6667 cubic meters of natural gas as heating power. If this is correct, my 900L of LPG would be the equivalent of 600 cubic meters of natural gas, which would yield a potential saving of between 100 and 200 euros/year on the bill. Does it sound right?

 

Cheers Nicholas

 

 

 

[Jeremy Cumberland]

 

 

I looked up the internet again and found a site which claims that 1L of LPG = 0.5kg of LPG = 5500kcal which would be equal to 0.6667 cubic meters of natural gas as heating power. If this is correct, my 900L of LPG would be the equivalent of 600 cubic meters of natural gas, which would yield a potential saving of between 100 and 200 euros/year on the bill. Does it sound right?

 

Cheers Nicholas

 

Your numbers look reasonable to me, but 5500 kcal/litre seems a little low for LPG. If it is low, then you would need more natural gas to provide the same energy. If you reckon on 630 cubic metres of natural gas against 900 litres of LPG, I don't think you'll go far wrong, and I expect you'll still get a decent saving.

 

Do Italian gas suppliers not price in euros per kWh or euros per MJ? UK gas prices are now per kWh.