Nuclear power as an energy source is seeing a huge resurgence worldwide.  As of October 2014, 436 reactors were operating across the globe, providing a total of 376 GW of electrical power.  However 546 further reactors are now under construction, planned or proposed to supply up to another 680 GW of electricity.

The energy production of nuclear plants has increased steadily over time, increasing revenues for plant operators according to an economy of scale. It is possible to double the amount of energy generated without doubling the cost of production, and this has driven plant expansion since the first nuclear plants were constructed in the early 1950s.

We are now seeing a paradigm shift in plant economics, moving from an economy of scale to an economy of volume. Instead of building larger and larger reactors, there is increasing interest in mass-producing small modular reactors (SMRs), where a number of small units can be sited together to meet power requirements. These SMRs have been proposed as suitable equipment for providing nuclear power to regions with dispersed populations, or low overall power needs, where a single large plant may not be appropriate.


The small Pacific island nation of Popolopo, a Spanish overseas territory situated between Fiji and Samoa, has decided to install a small nuclear power plant in order to supply energy for a sea water desalination facility.  The Spanish government has approached a number of nuclear powered nations to find a reactor vendor for the project, and several groups have responded to the invitation to tender with bids to supply nuclear equipment.  However, the government is not in a position to critically appraise the bids, nor to design a desalination facility.  For this they have approached you.

Your team represents an engineering consultancy firm hired by the government of Popolopo to assess the bids from the various nuclear equipment vendors and select the most appropriate to construct their nuclear power system on the island.

The islanders have limited access to fresh water.  There is enough water to drink, however this is insufficient for anything other than the most basic requirements.  Out of necessity, water is strictly rationed by the government.  Hopefully, the nuclear powered desalination plant will be able to supply enough water to comfortably meet the needs of the population of 750,000 people. There should be sufficient capacity for expansion of the population and an industrial base over the lifetime of the plant.

The Popolopan reactor will be a technology demonstrator.  If successful it is likely that other reactors of the same type will be constructed in Spain in the future.


First and foremost you will need to consider the Popolopan water needs, and how sea water can be processed to meet the requirements of the islanders.  The method of water desalination should be matched to the seawater feed and fresh water product required both in terms of quality and quantity.

The island’s government are committed to the nuclear reactor plan, and so for political reasons, the plant must be powered by the nuclear power facility.  You should consider the most appropriate way to use energy from a nuclear source to perform desalination, and whether given desalination and processing methods preclude the use of certain reactors, and vice versa.  You will also need to ensure that your solution is appropriate, remembering that Popolopo has no existing nuclear infrastructure, so provision for all necessary support and accident scenarios must be considered.  Consider also the group offering to supply the reactor technology, and whether they have the necessary experience and resources to deliver their design successfully.

Unlike the nuclear reactor design, which must be selected from the list of tenders that have been received, the desalination plant could be a commercial system or a novel or bespoke design.  Your choice of desalination plant should safely and effectively meet the water needs of Popolopo.  You will need to determine how much water you should aim to supply, what your method of desalination will be and which reactor is the best for this.  When selecting a reactor you should also consider the power rating, fuel type, regular outages for refuelling and regular fuel costs, proliferation risks, accident preparedness, technological readiness, and any other factors you deem relevant.

The initial outlay costs for the construction of the reactor are expected to be very high, and it is extremely unlikely that the Popolopan government will be able to shoulder the costs of construction alone.  If you can develop a strong enough case to show that the nuclear-powered desalination facility will be successful, you may be able to convince economic development organisations to invest in the project.  The government of Popolopo would need to meet the long term costs of the project without additional input.

You should give strong consideration to the sustainability effects of your plant, including economics, social effects, and environmental impact, both in the short and the long term.

Reactor Vendor Bids

The following reactor vendors have come forward with offers to supply reactor equipment to Popolopo.  You should research their designs and judge which is the most appropriate.  The government of Popolopo requires you to submit a full statement justifying your choice of design.

Reactor Designer Reactor Design Name Country of origin
OKBM Afrikantov KLT-40S Russian Federation
Babcock and Wilcox mPower United States of America
Toshiba 4S Japan
Bhabha Atomic Research Centre (BARC) AHWR300-LEU India
General Atomics EM2 United States of America
DCNS FlexBlue France
GE-Hitachi PRISM United States of America