With over 100 years of experience in the fuel industry, we believe there is no question or problem that Portland cannot answer or help you solve. We want to hear your questions and issues with regards fuel buying, fuel quality, fuel consumption, petrol forecourts, grades of fuel, refining etc, etc, etc. The list really is endless and we would like you the fuel user to test us so we can help you!

Feel free to send us a question. We will publish it on this page along with the best answer we can give. Please indicate if you wish to remain anonymous and we will publish the question without your name.

Read our forum questions below:

July 4, 2023 Can Carbon Capture and Storage destabilise geological formations in the same way as fracking?

Hydraulic fracturing, or fracking, is a process that uses high-pressure fluid injections to shatter rock formations and extract natural gas. Due to the high pressures involved, fracking is also associated with increased seismic activity and as a result can highly disrupt local geological formations.  In contrast, Carbon Capture and Storage (CCS) is a process whereby CO2 is “captured” from the air and then transported to a storage site where space already exists; for example a depleted oil or gas field or a deep rock reservoir, and as such, invasive and destructive processes are not required. Therefore, CCS does not destabilise geological formations in the same way that fracking does.

This question was sent in by Duncan from Oxford

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When carbon is stored underground, is it in the form of compressed CO2 gas? Does it get to the point of being compressed into liquid form?

Geologic carbon sequestration is the process of storing carbon dioxide (CO2) in underground geologic formations. The CO2 is usually pressurised until it becomes a liquid, and then it is injected into porous rock formations in geologic basins. Storage sites must generally be located at a depth of 800m or deeper, where prevailing pressures keep CO2 in either a liquid or a supercritical state. A supercritical fluid is a substance at a temperature and pressure above its critical temperature and pressure. The critical point represents the highest temperature and pressure at which the substance can exist as a vapour and liquid in equilibrium. Therefore, the CO2 is stored in its liquid form and not in a gaseous state.

This question was sent in by Duncan from Oxford

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February 14, 2023 How much does the UK rely on imports of fuel?

It often surprises people that the UK imports more fuel than it exports, considering our history as a North Sea oil producer. But the fact is, even in the heyday of North Sea crude oil production, the UK was still importing a great deal of oil. Historically this was because North Sea oil is of high quality and therefore commands a premium price on global markets. Therefore, producers preferred to sell their UK crude internationally (at a higher price), whilst UK refiners bought their crude from elsewhere and enjoyed lower purchase prices, as a result of buying lower quality crudes.

This practice still continues to this day, with complex UK refineries preferring to buy in lower grade, cheaper global crudes (which they can still easily process into refined products), whilst the more expensive North Sea blends go overseas to less sophisticated refineries which require high grade crude to produce high quality refined fuel such as gasoline and jet fuel.

This situation, however, has been compounded over the last 10 years with declining North Sea oil production. This has meant that the UK fundamentally uses more crude oil than we extract and so we have become ever more dependent on overseas crude for supply chain (rather than price) reasons.

A more pertinent issue today is just how reliant the UK has become on imported refined products. UK refineries are typically geared to the production of gasoline (petrol), which means that grades such as diesel and jet fuel (demand for which have grown hugely since the turn of the Millennium) have been imported in greater and greater volumes – much of it traditionally from Russia. So whilst the UK was only importing about 5% of its crude oil requirements from Russia in the run-up to the Ukrainian invasion, the equivalent figure for diesel was 25%. Obviously Russian product has now been sanctioned which is why finished products in the UK went up in price much more than crude in 2022.

This question was sent in by Mark from Leeds.

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December 23, 2021 Is the quality of supermarket fuel lower than other brands like Shell, Esso and BP?

Supermarket fuel is the same as branded forecourt fuel (BP, Shell, Esso et al) in that the basic product comes from the same refinery or fuel depot. This is because most fuel companies do not have their own supply-chain and instead rely on each other’s assets and / or 3rd party facilities, where they “co-mingle” their stock. So in the UK for example, the fuel at a Tesco Petrol Station in Southampton comes from the Esso Fawley refinery (nr Southampton), which also supplies the same fuel to branded Esso Petrol Stations on the South Coast.

So that’s the “no” bit, but it would be wrong to conclude that fuel in a Tesco site is exactly the same as an Esso site. This is because Esso add their own special additives to the fuel (cleaning agents, lubricity improvers, octane boosters etc), whereas the supermarkets typically just buy and sell basic / neat petrol and diesel. If the oil companies are to be believed, then you might conclude their fuel is higher quality. But in reality, the core product is the same whether you fill at a branded service station or a supermarket.

This question was sent in by Olivia from Manchester.

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July 6, 2021 Why is supermarket fuel generally cheaper than other forecourt brands?

Thanks for this question Natalie– it’s one that we often get asked.

The first idea we’d like to scotch is that supermarkets sell their fuel at a loss, which is a common misconception. In realty, it rarely happens – if ever. People might perceive that the supermarkets have buying advantage over other retailers of fuel (because of their size), but in reality, they buy at best, half a penny better than the standard wholesale market price. Where they do have an advantage however is on overheads and how that filters through to the unit rate sold at the pumps. So if you take a medium sized petrol station, with an annual throughput of 3m litres, as a minimum you are going to require 5 employed staff (Manager, cashiers, cleaners, maintenance etc, etc). 5 staff at an average UK salary of £25K gives a total overhead cost of £125,000. Divide that by the volume, and you have an overhead pence per litre (ppl) rate of 4.17ppl. This has to be added to the cost of the fuel sold.
A Supermarket filling station on the other hand, probably has no less than 3 dedicated workers, as much of the maintenance, service and management are integrated into the overall store operations. Even more significant is the average throughput of a typical supermarket site, which is circa 10m litres per annum. Take £75K (3 employees) and divide that by 10m litres and you have an overhead cost of 0.75ppl – basically 3.5ppl cheaper than an independent forecourt. Add in the likely buying advantage of 0.50ppl and you have fuel that can retail at 4ppl cheaper than an independent petrol station (and still make a decent turn on selling 10m litres per annum).

This question comes from Natalie, a Portland Pricing customer.

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May 4, 2021 What is E10 and how does it differ to Petrol?

The answer to this one is relatively simple Matthew; E10 is petrol with a 10% bio content.

Most European countries have a requirement to blend neat mineral oils (petrol and diesel) with a bio component, in order to reduce CO2 emissions. In the case of petrol, the bio component is ethanol, so the grade of fuel is called E(thanol) 10.

Neat (100%) petrol and E10 petrol are almost identical in terms of ignition and flammability characteristics, plus the use of E10 is allowed under engine warranties. However, E10 is what’s called hygroscopic, which means it has the capacity to hold water in suspension. Water in fuel is never a good idea, so it does mean that the storage of E10 in fuel tanks requires extensive tank maintenance and housekeeping to keep water out.

Unlike E10 petrol, you will not see B10 diesels, because engine manufacturers only allow 7% bio content (ie, B7) in diesel. Diesel bio can come from many things (Used Cooking Oil, Palm Oil, Tallow), as opposed to petrol bio, which is almost always ethanol based.

This question came from Matthew in Lincoln who was enquiring about sustainable fuel options in May 2021.

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