[en] This thesis will describe a method for an arbitrage-free evaluation of forward and futures contracts in the Nordic electricity market. This is a market where it is not possible to hedge using the underlying asset which one normally would do. The electricity market is a relatively new market, and is less developed than the financial markets. The pricing of energy and energy derivatives are depending on factors like production, transport, storage etc. There are different approaches when pricing a forward contract in an energy market. With motivation from interest rate theory, one could model the forward prices directly in the risk neutral world. Another approach is to start out with a model for the spot prices in the physical world, and then derive theoretical forward prices, which then are fitted to observed forward prices. These and other approaches are described by Clewlow and Strickland in their book, Energy derivatives. This thesis uses the approach where I start out with a model for the spot price, and then derive theoretical forward prices. I use a generalization of the multifactor Schwartz model with seasonal trends and Ornstein Uhlenbeck processes to model the spot prices for electricity. This continuous-time model also incorporates mean-reversion, which is an important aspect of energy prices. Historical data for the spot prices is used to estimate my variables in the multi-factor Schwartz model. Then one can specify arbitrage-free prices for forward and futures based on the Schwartz model. The result from this procedure is a joint spot and forward price model in both the risk neutral and physical market, together with knowledge of the equivalent martingale measure chosen by the market. This measure can be interpreted as the market price of risk, which is of interest for risk management. In this setup both futures and forward contracts will have the same pricing dynamics, as the only difference between the two types of contracts is how the payment for the contract is settled. To demonstrate the performance of my model, I will find different forward curves with different delivery times and compare them with actual forward curves from Akershus energy. Then I deduce an option price with a forward/futures as an underlying asset. The option price, will be a generalized version of the Black 76 model. Black 76 is the most applicable and used option pricing model in the Nordic energy market. The thesis is organized as follows: Chapter 1 has been a general introduction to the electricity market, and the topics I will look at in this thesis. In chapter 2 I will look at some properties of the energy prices. In chapter 3 and 4, I introduce the model for the spot price dynamics, and look at some properties for the model. I also discuss equivalent Martingale measure in view of this. I derive the forward/futures prices and I look at some fitting techniques to estimate my variables in chapter 5 and 6. In chapter 7 I will present the performance of the model. I deduce an option price in chapter 8. Chapter 9 will be a discussion of my findings. Some basic theorems and solution algorithms are left to an appendix. The main objectives of this thesis were to derive a formula for arbitrage free pricing of forward and futures contracts in the energy market, and also derive an option price using the forward as an underlying asset. The first chapters provided me with the material I needed to derive these formulas. In chapter 7 I tested my theoretical model against forward curves in the market. There are several possible explanations for the results from chapter 7. One possibility is that. the stochastic spot model is poor for electricity prices, and perhaps works better for other energy markets. My Ornstein-Uhlenbeck process is only driven by Wiener noise and no Levy noise. An inclusion of a Levy term could increase the prediction in case of sudden shifts in the spot price. The Nordic electricity market is a new market, which is very sensitive to sudden changes. Forward pricing in this market may not be as precise as in other markets , which explains the instability of some results. My main result is that my model works for short-term contracts, but my risk parameter is not stable enough to make good estimates for long-term contracts. In chapter 8 I derived an option price for both European and American options. The problem with incompleteness, which arises when valuing energy-options on the spot price, is not a problem for these options. The forward contract is in itself storable, and therefore the market is complete for these options. Another reason why my model should work is that the cash flow of the forward contract takes place at the contracts maturity date. The result is that the option is always worth more than the forward contract, and the exercised option is worth the same as the forward contract. Note that this is not the case for futures. (Author)