**4. Economics of electricity generation**

#### **4.1. Recovery cost of uranium resources**

For the economic electricity generation, it is preferable that uranium recovery cost is cheaper. With the recent price increase in the market, the highest cost category of <260 \$/kgU for conventional uranium resources is added to Red Book 2009 [21]. On the other hand, the recovery cost of unconventional uranium is higher than 260 \$/kgU as mentioned in Section 3.1. Therefore, the cost of 260 \$/kgU is considered as a criterion to determine whether a resource can be recovered economically or not.

**Figure 5** shows the market price of uranium in the past decade [22]. The price increased abruptly to over 300 \$/kgU in June 2007. However, this is a spot price that was not directly employed in trading. Generally, uranium is traded at its forward price. The average price of uranium purchased by owners and operators of US civilian NPP was 120 \$/kgU (46.16 \$/lbU<sup>3</sup> O8 ) in 2014 [23]. As shown in **Figure 6** [23], the price increased slowly from 2004, and the sharp increase in 2007 was related to the spot market price. In the present study, the current trading price of 120 \$/kgU is employed as representative uranium price of conventional resources.

In general, it is believed that unconventional uranium resources such as uranium from seawater are difficult to recover economically. However, an effective recovery method based on a new type of polymer braid has been developed at Japan Atomic Energy Agency (JAEA) [17]. The uranium concentration of 3.3 ppb in seawater is extremely low, but the economic recovery can be achieved with the advantage of efficient absorbents synthesized by radiation-induced graft polymerization and an ocean current. This method can compensate for the difficulty in recovery from low concentration solution. The economic recovery was proved by evaluation with a detailed system design based on the ability to recover confirmed by experiment.

> The seawater uranium can be extracted economically even by current technology with the cost of 208 \$/kgU, which is lower than the criteria of 260 \$/kgU. However, the cost is higher than the trading price of 120 \$/kgU, even though the lower cost of 110 \$/kgU can be achieved in the future. As a result, it is concluded that the cost of seawater uranium with current technology itself is not reasonable even though seawater uranium can be considered as economically

Safety and Economics of Uranium Utilization for Nuclear Power Generation

http://dx.doi.org/10.5772/intechopen.72647

29

The cost of seawater uranium recovered with current technology is not sufficiently low. However, the economy of electricity generation should be assessed not for uranium purchase cost but for the entire cost. In this section, characteristics of electricity generation cost for NPG

The electricity generation costs of LWR were evaluated with conventional uranium and seawater uranium in Ref. [24] reflecting on the latest condition investigated by the cabinet of Japan [25]. The cost of LWR was evaluated assuming the PWR plant with electric power (gross) of 1300 MWe. In addition, the costs of HTGR were evaluated as well. That is evaluated based on a gas turbine high-temperature reactor 300 (GTHTR300) [26] designed by JAEA as a heliumcooled and graphite-moderated commercial scale HTGR with 600 MWt thermal power and 850°C outlet coolant temperature. The GTHTR300 is combined with four reactor units in a plant. Total thermal power of the plant is 2400 MWt, and gross electric power is 1100 MWe. The cost of HTGR is cheaper than LWRs due to the cheaper construction cost and higher thermal efficiency of 45.6% [26] than LWRs of approximately 33%. The construction costs are compered in **Figure 7**. The cost of HTGR, only for the reactor component, is larger than that of LWR due to the lower power density design to offer higher levels of safety. Other parts of

**4.2. Electricity generation cost using seawater uranium recovery cost of uranium** 

**Figure 6.** Weighed average price of uranium purchased by owners and operators of US civilian NPPs [23].

recoverable resources.

and the cost with seawater uranium are discussed.

**resources**

About 1.5 gU/kg adsorbent of uranium was successfully recovered from seawater in Okinawa over a 30-day period. From these tests and trials, the potential cost of uranium recovery, considering a scaled-up annual recovery of approximately 1200 tU/year, was evaluated. The cost is composed of adsorbent production (69%), uranium recovery (29%), and elution and purification (2%). In this estimation, six repeated soaking cycles are assumed. To realize the economic recovery, the duration of absorbent is important because the cost mainly depends on adsorbent production. The realistically achievable cost with current technology using braids with 18 repeated soaking cycles is 208 \$/kgU with the exchange rate of 120 yen/\$ [17]. In the future, a more reasonable cost of 110 \$/kgU [17] can be realized using braids with 60 repeated soaking cycles.

**Figure 5.** Spot market price of uranium.

Therefore, the cost of 260 \$/kgU is considered as a criterion to determine whether a resource

**Figure 5** shows the market price of uranium in the past decade [22]. The price increased abruptly to over 300 \$/kgU in June 2007. However, this is a spot price that was not directly employed in trading. Generally, uranium is traded at its forward price. The average price of uranium pur-

As shown in **Figure 6** [23], the price increased slowly from 2004, and the sharp increase in 2007 was related to the spot market price. In the present study, the current trading price of 120 \$/kgU

In general, it is believed that unconventional uranium resources such as uranium from seawater are difficult to recover economically. However, an effective recovery method based on a new type of polymer braid has been developed at Japan Atomic Energy Agency (JAEA) [17]. The uranium concentration of 3.3 ppb in seawater is extremely low, but the economic recovery can be achieved with the advantage of efficient absorbents synthesized by radiation-induced graft polymerization and an ocean current. This method can compensate for the difficulty in recovery from low concentration solution. The economic recovery was proved by evaluation with a detailed system design based on the ability to recover confirmed by experiment.

About 1.5 gU/kg adsorbent of uranium was successfully recovered from seawater in Okinawa over a 30-day period. From these tests and trials, the potential cost of uranium recovery, considering a scaled-up annual recovery of approximately 1200 tU/year, was evaluated. The cost is composed of adsorbent production (69%), uranium recovery (29%), and elution and purification (2%). In this estimation, six repeated soaking cycles are assumed. To realize the economic recovery, the duration of absorbent is important because the cost mainly depends on adsorbent production. The realistically achievable cost with current technology using braids with 18 repeated soaking cycles is 208 \$/kgU with the exchange rate of 120 yen/\$ [17]. In the future, a more reason-

able cost of 110 \$/kgU [17] can be realized using braids with 60 repeated soaking cycles.

O8

) in 2014 [23].

chased by owners and operators of US civilian NPP was 120 \$/kgU (46.16 \$/lbU<sup>3</sup>

is employed as representative uranium price of conventional resources.

can be recovered economically or not.

28 Uranium - Safety, Resources, Separation and Thermodynamic Calculation

**Figure 5.** Spot market price of uranium.

**Figure 6.** Weighed average price of uranium purchased by owners and operators of US civilian NPPs [23].

The seawater uranium can be extracted economically even by current technology with the cost of 208 \$/kgU, which is lower than the criteria of 260 \$/kgU. However, the cost is higher than the trading price of 120 \$/kgU, even though the lower cost of 110 \$/kgU can be achieved in the future. As a result, it is concluded that the cost of seawater uranium with current technology itself is not reasonable even though seawater uranium can be considered as economically recoverable resources.
