Cogeneration

INTRODUCTION

Since 1 January 2005 a combined heat and power (CHP-) certificate system has been in effect in the Flemish Region, for the promotion of primary energy savings through the use of qualitative CHP-facilities for the generation of electricity and heat.

This is a two-pronged system. On the one hand each power supplier is obligated to ensure a minimum electricity share from qualitative CHP-facilities. On the other hand owners of qualitative CHP-facilities (COGENERATION producers) can request combined heat and power certificates from the VREG.

The following technologies are considered to generate heat and power in the Flemish Region:

• Back pressure steam turbine
  Steam turbine, in which steam enters the turbine under high pressure and exits the turbine under lower pressure. The steam on the low pressure side is subsequently used for useful heat applications
• Steam condensing extraction turbine
  Steam turbine, in which steam enters the turbine under high pressure and from which a portion of the steam is drawn at lower pressure for useful heat applications. The rest of the steam is further expanded through the turbine, and subsequently fully condenses into water in a condenser
• Gas turbine with heat recovery
  Turbine driven by the internal combustion of natural gas. The heat in the emission gases is used for the generation of steam, hot water or hot air or for another form of heat recovery.
• Steam and gas turbine with heat recovery
  A gas turbine with heat recovery for the generation of steam, and where the steam is fed into a steam condensing extraction turbine
• Internal combustion engine
  Piston engine driven by natural gas, diesel or biofuel, whereby the released heat from the engine cooling and burnt gases is applied in a useful manner.
• Stirling engine
  External combustion engine in which air is displaced back and forth between hot and cold spaces. The air in the hot space expands when absorbing heat and pushes up on a piston, after which the air moves back to the cold space, cools off and contracts.
• Fuel cell
  Electrochemical device that converts chemical energy directly into electrical energy in an ongoing reaction, whereby, contrary to batteries, new reactants can be constantly replenished from the outside. Depending on the type of fuel cell a high or low quantity of heat is released in this process, which can be applied in a useful manner.
• Steam engine
  Engine that partially converts the energy from hot pressurised steam into mechanical energy. Typically this takes place by expanding the steam in one or more pistons and transferring the expansion energy to a flywheel.
• Organic Rankine Cycle
  Closed cycle whereby, as in a traditional power plant, a medium is heated into gaseous form at high pressure and subsequently expands on a turbine and condenses. Whereas this medium in traditional power plants is always water converted into steam, in the Organic Rankine Cycle a medium with a lower evaporation value than water is used (e.g., butane or ammonia), in order for it to be able to be converted at relatively low temperatures into a gaseous state and to power a turbine.
• Other technologies and combinations thereof that satisfy the definition of CHP-facility in accordance with the Electricity decree, namely "the creation in a single process of heat and electricity and/or mechanical energy"
  

THE AWARDING OF CHP-CERTIFICATES

CHP-producers can obtain CHP-certificates from the VREG for the primary energy savings achieved by CHP- facilities in the Flemish Region, that satisfy the conditions for qualitative CHP-facilities.

A CHP-certificate shows that 1.000 kilowatt hours (kWh) primary energy were saved in a qualitative CHP- facility compared to a situation in which the same quantity of electricity and/or mechanical energy and heat are generated separately. Combined heat and power producers who are awarded a CHP-certificate will not receive it in paper form. The certificates are issued by the VREG in a central database, which can be consulted by producers via the Internet.

Producers can sell these CHP-certificates to electricity suppliers that still have to meet their certificate obligation. If the CHP-producer is also the electricity supplier, they can use the certificates to meet their own certificate obligation.

For detailed information see Combined heat and power producers (Dutch)

CHP-CERTIFICATE OBLIGATION

Minimum electricity share from qualitative cogeneration

In Flanders each electricity supplier has been obliged since 2005 to contribute to the saving of a specific quantity of primary energy by means of qualitative cogeneration. The quantity of primary energy to be saved corresponds to a specific minimum electricity share of the total supplied to customers. In 2005 this minimum share amounted to 1.19%. This will increase to 5.23% as of 2012.

CHP-certificates as proof of compliance with the minimum electricity share from qualitative cogeneration

Annually suppliers are to deliver a specific number of CHP-certificates to the VREG before 31 March of the following year. This will increase to 5.23% as of 2012.

The number of CHP-certificates to be submitted by an electricity supplier is referred to as the supplier's CHP-certificate obligation. Annually the VREG calculates the number of CHP-certificates to be submitted by each supplier in order to meet this certificate obligation. The VREG will inform the supplier of this number after which the supplier is to submit this number of CHP-certificates to the VREG.

If a supplier is also a producer and therefore saves their own primary energy by making use of qualitative combined heat and power, they can request CHP-certificates from the VREG for the primary energy savings achieved by their own facilities. In the other case they can purchase the CHP-certificates on the market from the producers.

Acceptability of CHP-certificates

Not all CHP-certificates can be used to meet the CHP-certificate obligation.

The VREG only accepts certificates awarded for primary energy savings achieved by making use of a qualitative CHP-facility situated in the Flemish Region and put into operation on or significantly altered after 1 January 2002.

For the first four years after the date of start-up of a CHP-facility, CHP-certificates will be awarded for the full primary energy savings. From the fifth year after start-up, CHP-certificates that can be used for the certificate obligation will be awarded for X% of the primary energy savings. For the remaining part of the primary energy savings (100-X%) certificates will be awarded that can not be used for the certificate obligation. For detailed information see Article 14, §1 of the Flemish Government Decree on the promotion of electricity production in qualitative combined heat and power facilities (only available in Dutch).

The VREG records CHP-certificates that can be used for the certificate obligation, as well as those that cannot be used, in the central database.

CHP-certificates awarded for the production of electricity exported abroad, may no longer be submitted in order to meet the certificate obligation in the Flemish Region.

Administrative fine

If an electricity supplier submits the correct number of CHP-certificates, they meet their CHP-certificate obligation. If they submit too few certificates, they have to pay an administrative fine of 45 euros per missing CHP-certificate.

The administrative fine is to be paid to the Energy fund. This fund can be used by the Flemish Government for the financing of its cogeneration policy, among others.

For detailed information see Combined heat and power producers (Dutch)