“But one should not forget that wind turbines work only a quarter of the time approximately. So we need clean energy to meet energy demands the rest of the time.”

Placing a wind turbine where the wind only blow a quarter of the time would be a very badly chosen location.

The wind blow more often than this, but it may blow with less than maximum strength. That means the wind turbine will be generating power more often than you state but at a lower power level.

Stating capacity factor for a wind turbine at a given location gives an average over time of the percentage of maximum rated power. Depending on location a wind turbine will give 25% – 40% of its rated power, with 40% at off-shore locations.

Note that all power plants have capacity factors less than 100%. Hydro plant are typically 25% – 60% because there is not enough water to run them at maximum power all the time. However we can control the water flow and that makes them a good combination with wind energy where we know the average power generation over time but cannot control when it arrives.

“Denmark gets 13 percent of its electricity demand by wind, yet it has one of the most polluting electricity generation of the European Union with 881 grams of CO2 per kWh.”

This comes from that Denmark has traditionally relied on coal fired power plants. It is worth noting that Danish power plants besides the electricity generation use the waste heat for district heating. In many other countries the heat is simply wasted in cooling tower and rivers.

“But one should not forget that wind turbines work only a quarter of the time approximately. So we need clean energy to meet energy demands the rest of the time.”

Placing a wind turbine where the wind only blow a quarter of the time would be a very badly chosen location.

The wind blow more often than this, but it may blow with less than maximum strength. That means the wind turbine will be generating power more often than you state but at a lower power level.

Stating capacity factor for a wind turbine at a given location gives an average over time of the percentage of maximum rated power. Depending on location a wind turbine will give 25% – 40% of its rated power, with 40% at off-shore locations.

Note that all power plants have capacity factors less than 100%. Hydro plant are typically 25% – 60% because there is not enough water to run them at maximum power all the time. However we can control the water flow and that makes them a good combination with wind energy where we know the average power generation over time but cannot control when it arrives.

“Denmark gets 13 percent of its electricity demand by wind, yet it has one of the most polluting electricity generation of the European Union with 881 grams of CO2 per kWh.”

This comes from that Denmark has traditionally relied on coal fired power plants. It is worth noting that Danish power plants besides the electricity generation use the waste heat for district heating. In many other countries the heat is simply wasted in cooling tower and rivers.

http://en.cop15.dk/news/view+news?newsid=2117

http://en.cop15.dk/news/view+news?newsid=2117

I really appreciate wind energy and think this expansion is good news.

But one should not forget that wind turbines work only a quarter of the time approximately. So we need clean energy to meet energy demands the rest of the time.

Denmark gets 13 percent of its electricity demand by wind, yet it has one of the most polluting electricity generation of the European Union with 881 grams of CO2 per kWh.

The EU average is of 353 grams. France, in comparison produces only 83 grams per kWh thanks to nuclear and hydro. Japan and the United States are around 600 grams per CO2 per kWh.

So wind should be complemented by clean coal with CCS (if it comes one day) and we should keep in mind that we need other low carbon energy sources.

I really appreciate wind energy and think this expansion is good news.

But one should not forget that wind turbines work only a quarter of the time approximately. So we need clean energy to meet energy demands the rest of the time.

Denmark gets 13 percent of its electricity demand by wind, yet it has one of the most polluting electricity generation of the European Union with 881 grams of CO2 per kWh.

The EU average is of 353 grams. France, in comparison produces only 83 grams per kWh thanks to nuclear and hydro. Japan and the United States are around 600 grams per CO2 per kWh.

So wind should be complemented by clean coal with CCS (if it comes one day) and we should keep in mind that we need other low carbon energy sources.

With companies such as Seatower now addressing the dependence on installation vessels and with new turbine manufacturers entering the market (ref. GE/Scanwind), the grid is now the biggest long term concern regarding offshore wind.

With companies such as Seatower now addressing the dependence on installation vessels and with new turbine manufacturers entering the market (ref. GE/Scanwind), the grid is now the biggest long term concern regarding offshore wind.