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Lisø PhD Dissertation Manuscript - NTNU

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772 Nordvik and <strong>Lisø</strong><br />

0<br />

Â<br />

Â<br />

= p dV ( M) + p dV ( M)<br />

2s 2 2s 2s 2 2s<br />

CM<br />

s∈S TM<br />

s∈S 2s 2 2s<br />

2s − ( Â p dV ( M)<br />

+ Â p<br />

2 2s<br />

CM<br />

s∈S TM<br />

s∈S dV ( M))<br />

is inserted into Equation 10a and the expression is<br />

rearranged:<br />

1 1 1 1 1<br />

NV( M) = v ( Wˆ, z ) −c( Wˆ,<br />

z ) −m<br />

2s 2 2s<br />

+ p dV ( M)<br />

Â<br />

s∈S Â<br />

2s 2 2s 2s<br />

+ p d { V ( C) −V<br />

( M)}<br />

CM<br />

s∈S Â<br />

+ −<br />

2s 2 2s p { dT<br />

2s<br />

V ( M)}<br />

(12)<br />

TM<br />

s∈S Into this expression, some definitions are inserted:<br />

C<br />

C =<br />

2s 2 2s 2s<br />

p d { V ( C) −V<br />

( M)}<br />

C<br />

Â<br />

s∈S CM<br />

Â<br />

= p { dT −V(<br />

M)}<br />

T 2s 2 2s 2s<br />

s∈S TM<br />

The symbols CC and CT are the expected values of the<br />

possibility to choose the strategy in period 2 whenever<br />

this is advantageous. Hence, they are real option values.<br />

The definitions of SCM and STM ensure that these are<br />

positively signed. Their size depends, among other<br />

things, on the level of effort put into maintenance.<br />

V<br />

1 1 1 1 1<br />

N ( M) = v ( Wˆ, z ) −c ( Wˆ,<br />

z ) −m<br />

2s 2 2s<br />

C T<br />

+ p dV ( M)<br />

+ C + C<br />

(12b)<br />

Â<br />

s∈S Using these definitions, one find that the (expected)<br />

value of a building, which in period 1 is optimally<br />

maintained, can be expressed as the sum of four<br />

components:<br />

• the net value of the building in use in the first<br />

period;<br />

• the expected value of the building in period<br />

2, aggregated over all possible states, if it is<br />

optimally maintained;<br />

• the value of the real option to convert the building<br />

if this is profitable when the future climate<br />

conditions are observed; and<br />

• the value of the real option to scrap the building<br />

if this is profitable when the future climate<br />

conditions are observed.<br />

The normal action taken by an owner of a building is to<br />

maintain it in a suitable way. The decision to convert or<br />

to scrap is a more drastic, and less frequent, decision.<br />

In the remaining parts of the paper, the choice of<br />

the maintenance strategy will be termed ‘continued<br />

ordinary use’.<br />

This apparatus can be used for an informal characterization<br />

of the result on the mutual dependency between<br />

the maintenance efforts made in period 1 and the<br />

conversion and scrapping probabilities, referred above:<br />

Up to a certain point the net value of the building in use<br />

in the first period is increasing in m 1 . The period 2 value<br />

of the building if it is not scrapped or converted is<br />

increasing in m 1 , because this, in every state, increases<br />

the state of the building as measured by z. The value of<br />

the real options, and the probability that they will be<br />

exercised, will however be decreasing in m 1 . Hence,<br />

there is a trade-off between actions that enhance the<br />

value of the building in continued ordinary use and<br />

actions that enhance the value of the possibility to adapt<br />

the building to changed future weather conditions.<br />

The uncertain risks of future climate change can be<br />

interpreted as a situation where probabilities of states<br />

where conversion activities and scrapping take place are<br />

higher than they are under a steady state. Under this<br />

interpretation, one can say that increased climate uncertainty<br />

implies that owners will give more weight to<br />

actions that increase the value of the possibilities to<br />

utilize future climate information. From the arguments<br />

above, it is seen that this means that effort put into<br />

maintenance prior to the realization of a given climate<br />

change scenario is decreasing due to the uncertainty<br />

related to the likely range and nature of future weather<br />

scenarios.<br />

The conversion strategy<br />

The value of an optimally designed conversion strategy<br />

in period 1 can be written as the sum of the value of the<br />

building in ‘continued ordinary use’ and the value of<br />

the real options associated with conversion or scrapping.<br />

The reformulation of the expression for NV(C) is<br />

done the same way that NV(M) was reformulated in<br />

Equation 12:<br />

1 1 1 1<br />

NV( C) = v ( W, z ) −c( W, z ) −C(<br />

W,W ˆ )<br />

2s 2 2s<br />

C T<br />

+ p dV ( M)<br />

+ V + V<br />

(13)<br />

Â<br />

s∈S Where the real options are:<br />

V C<br />

2s 2 2s 2s<br />

= p d { V ( C) −V<br />

( M)}<br />

Â<br />

CC<br />

s∈S Â<br />

V T 2s 2 2s 2s<br />

= p d { T −V<br />

( M)}<br />

TC<br />

s∈S Some remarks on the conversion technology can be<br />

given. At the start of period 1, the clay-factor has a value<br />

Wˆ . Then consider two alternative values Wˆ < W a < W b .<br />

Define<br />

C(Wˆ ,Wb ) = C(Wˆ,W a ) + d2C(Wa ,Wb ) + K (14)<br />

where K < 0, as a normal conversion cost structure.<br />

Hence, it is more expensive to make a two-step<br />

conversion than to do all the conversions in one single

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