AssosTech · Energy
  1. Start
  2. The view
  3. Services
  4. Numbers
  5. Work
  6. Method
  7. Origin
  8. Notes
  9. Contact

Oil and gas engineering, United Kingdom

Closer to the answer.

Assos Tech is a small oil and gas engineering consultancy. We work on producing fields, onshore and offshore, for the operators who run them and the people who finance them. Production, facilities, produced water, wells, gas projects and the technical review behind a purchase or a loan.

See the workWhat we do
In short

You send us the problem and the data. We check the numbers, find what is limiting production, and tell you what to do next and what it is worth.

Every figure we give you carries its source and its date. Where something is an estimate or a judgement, we say so. You can always see where the measurement ends and our view begins.

IThe work

The limit is usually somewhere else

A reservoir forecast is only useful if the wells can deliver it, the flowlines can carry it, the plant can separate it, the water can be disposed of and the economics still hold. On a mature field those links fail in turn. Remove one limit and the next one appears, usually in another team's spreadsheet.

We follow the chain from reservoir to export and we name the next limit before the first one is removed. Most of the work is arithmetic. A liquid capacity is converted to oil at the water cut of the wells being moved. A well is counted once. A planned date stays a planned date until there is an acceptance record.

Our clients are operators of large onshore fields in the Middle East and mature offshore assets in the North Sea, developers of gas projects in West Africa, and the investors and lenders behind them. They come to us when a decision is close: whether to approve a concept, how to restart a train, where the water will go, or what an asset is worth once its water, integrity and abandonment are priced in.

We are small on purpose. The engineer who scopes the work does the work and signs it.

How we work

Where the limit usually sits

From reservoir to export. The three streams that leave separation, and the point in the chain where each limit usually appears.

Conceptual, not for construction
ReservoirWellsFlowlinesGatheringSeparationOilStorage and exportGasFuel, sales, flareWaterTreatment, disposal, pondswell potentialintegrity, sizebackpressure, routingoil, water, gas limitsThe chainFor each link: what it has to carry, what it can carry, and what happens when it is full.
Figure 1. Removing one bottleneck exposes the next. For each link we check what it has to carry, what it can carry, and what happens when it is full.
Figure 1 · ConceptualIssued 18 October 2026 · Rev 0
IIServices

What we do

Seven service lines. Most jobs start in one and end up touching two or three, because the limit moves.

Specialist studies, field services and formal certifications are done with qualified partners where the job needs them. Reserves certification, competent person reports and legal opinions are outside our scope.

IIIBy the numbers

Four numbers from recent work

Each one comes from a named document. None of them is a portfolio total.

Planned oil, four-phase restart

86.6mbd

Four phases of 21.7, 22.3, 22.1 and 20.5 thousand barrels a day. Wells brought on one at a time.

Train restart plan, 2026

Flowline ranked for replacement

67.7km

Candidate lines ranked on integrity risk, production value and overlap with other scope.

Decision paper, 2021

Hold points before first flow

5

Each released only on evidence from the field, from valve line-up to stable receipt.

Commissioning plan, 2026

Scenarios carried to 2029

3

No transfers, transfers, transfers with optimisation. Each well counted once. Water followed to disposal.

Forecast workbook, September 2026

IVSelected work

Selected work

Fourteen anonymised cases from onshore and offshore fields. Each one says what the setting was, when it was done, and on what basis. Clients, fields and facilities are not named.

Featured · Middle East

Field forecast to 2029 with water limits

A three-scenario oil and water forecast across five central processing facilities, with transfer line, facility and disposal limits applied to every well and each well counted once.

Operator engagement

Read the case

At three of four facilities the water limit sits below the oil limit

Receiving-facility planning capacities for oil and produced water, four central processing facilities, with the dates each capacity was assumed available.

Thousand barrels per day050100150200250CPF A200 oil220 water, from Q2 2027CPF B207 oil117 waterCPF C70 oil37 waterCPF D245 oil, oil from Q4 2027100 waterPlanning assumptions used in the September 2026 forecast exercise, anonymised. Not published or verified operating limits.
Figure 2. A transferred well brings its water with it. Where the water bar is shorter, the water limit binds first.

Source: forecast planning inputs, September 2026, operator withheld. Transfer lines between facilities assumed at 40 and 50 mbd liquid.

Figure 2 · Plan values, labelledIssued 18 October 2026 · Rev 0
Middle East·Concept to first flow

A new 16-inch transfer line, from concept to first flow

We set the concept, worked the design through with the operator and the vendor, wrote the commissioning procedure with five hold points, supported execution and brought the line into service.

Met4 of 4 success criteriaOperator engagementRead the caseMiddle East·Producing field, water system planning

A produced water balance for a water-flooded field

Seven water streams tracked separately at each facility, disposal headroom taken at actual injection pressure, and the oil effect of each water limit stated.

Met4 of 4 success criteriaOperator engagementRead the caseWest Africa·Concept and pre-FEED

Sizing a gas pipeline from the pressure envelope

A concept and pre-FEED study that compared candidate diameters across the full pressure envelope before fixing the line size, and set out the FEED deliverables with the data each needs.

Met4 of 4 success criteriaAssos studyRead the case
All fourteen cases

Figures in the cases are planning values or dated study inputs and are labelled as such. They are not measured results and they do not imply client endorsement.

VHow we work

How we work

The same steps on every job, whether it takes two weeks or a year.

  1. i

    Agree the question

    Who decides, what they have to decide, and by when. Scope, interfaces and deliverables are written down before we start.

  2. ii

    Fix the data

    Each source is logged with its date. Measured values, operator statements, estimates and our own judgement are kept apart. Where sources disagree we show both and say which one we used.

  3. iii

    Follow the chain

    Reservoir, wells, flowlines, gathering, separation, water, gas, power, export. For each link: what it has to carry, what it can carry, and what happens when it is full.

  4. iv

    Give an answer

    Approve, approve with conditions, hold, or do not approve. The missing items are listed with an owner. Then the register, model or procedure your team can run without us.

VIThe name

The name

Assos is a Greek town on the Aegean coast. Aristotle set up his first school there in 347 BC and began working from what he could observe and measure. In modern Greek the word also means the ace. We took the name for the method, and the three words below are how we try to keep to it.

Observe

Start from the measured data, with its dates and its gaps. A model is only useful once it explains what the plant is doing today.

Endure

Build registers, models and procedures that still work after the engineer who built them has moved on. One live file per document, with the revision and the basis date inside it.

Vantage

Stand where the whole chain is visible, from reservoir to export to cash, and name the next limit before the first is removed.

The origin of the name

VIINotes

Notes

Short notes on the mistakes that keep coming up in forecasts, commissioning plans and water balances.

Production systems·October 2026

Liquid is not oil

A transfer line rated at 50 thousand barrels a day of liquid does not add 50 thousand barrels of oil. On a field at 60 per cent water cut it may add 20, and only if the receiving facility can dispose of the other 30.

ReadCommissioning·October 2026

A planned date is not a commissioning date

Forecasts, decks and handover notes keep promoting the date on a project plan into the date a line was available. The difference is a log, a line status and an operations signature.

ReadProduced water·October 2026

Produced water sets the field limit

Water is treated as a downstream reporting item until the day it decides how much oil the field can produce. On a mature water-flooded field that day has already arrived.

Read
AssosTech · Energy · Engineering

Tell us the decision you have to make

Send us the problem and the files behind it. Within a week we will tell you what evidence it needs, how long it will take and what it will cost.

Describe the decisionWrite to us

hello@assostechltd.com · 5 South Charlotte Street, Edinburgh, EH2 4AN