Some French vintners (search) started their earliest harvests ever Tuesday and a fire near a railroad station in Germany delayed trains -- some of the latest difficulties Europe faces as a deadly heat wave (search) scorches the continent.

French utility giant EDF asked customers to shut off lights and take other steps to conserve electricity in what meteorologists say is one of Europe's hottest summers in generations.

Power plants in Germany and France were granted temporary government approval to discharge water into rivers at higher temperatures than normal. In France, a limited number of power plants have reduced their energy output or shut down altogether.

"We are mobilizing all possible means to develop production," Francois Roussely, EDF chairman, told RTL radio. "The biggest danger would be to lose electricity."

The head of France's emergency hospital physicians' association said at least 100 people in France alone have died of heat-related illnesses since a stifling blanket of hot air settled over Europe. Temperatures have hovered around 100 in many countries for days, breaking heat records across Europe.

Patrick Pelloux called on the Red Cross (search) and even the army to lend a hand to medical facilities stretched to their limits.

"We are in an extremely difficult and tragic situation," Pelloux said. "With more people, we would be able to save lives."

France Info Radio reported that 500 people had been admitted to emergency rooms in the Paris region with heat-related illnesses.

Health Ministry spokesman Mathieu Monnet said it was difficult to determine if the deaths were weather-related but statistics on the number of deaths were being compiled.

Outside France, authorities have counted about 45 heat-related deaths. On Monday, five people died in Spain while fleeing a fire.

Wildfires fanned by hot winds have eaten up tens of thousands of acres of territory in Italy, France, Greece, Spain, Portugal, Croatia, and the Netherlands.

Algeria dispatched more than 80 firefighters and more than a dozen water tanker trucks to the French Mediterranean port city of Marseille to help battle fires in southeast France.

Italian firefighters were battling 21 blazes in numerous regions, officials there said. Alpine rescue teams helped evacuate about 100 hikers whose path was blocked by a fire near the town of Misurina, 90 miles north of Venice.

Temperatures in Switzerland set a new record, the Swiss Meteorological Office said Tuesday. In eastern Switzerland, the mercury hit 107 on Monday, easily topping the previous high of 102 set in 1952.

In Germany, national railroad Deutsche Bahn said a fire that broke out early Tuesday near Hamburg's Altona station delayed 15 trains but was extinguished within an hour.

Train service between Berlin and the eastern city of Halle returned to normal overnight after overhead wires had to be switched off late Monday to allow rescue services access to a forest fire, the German national railroad said.

High temperatures also caused spikes in pollution. Reduced speed limits went into effect in areas of southern Switzerland because of high ozone levels.

Nature's rhythms also were disturbed: The harvest began weeks earlier than usual in France's Beaujolais winemaking region, where grapes have ripened quickly under a pounding sun.

Three vintners asked authorities for permission to start the harvest Tuesday in the central French region known for its light, fruity wines. Many more winemakers plan to begin harvesting Thursday, said Anne Masson of the Interprofessional Union of Beaujolais Wines.

The Beaujolais harvest has never come so early in the season. Before now, the earliest harvest was in 1893, when it began Aug. 25. Usually, ripe grapes are gathered sometime in September.

Grouse hunters in Scotland were warned Tuesday that the birds might be hard to find because they may have gone off looking for water.

Britain's Environment Agency said Tuesday it rescued about 1,000 fish from a river in western England that had dried up, leaving the fish stranded in small pools with dwindling oxygen supplies.

Italian weather experts say Europe's heat wave is one of the five worst in the last 150 years. Intense monsoon activity in Africa has been blamed in part for the merciless temperatures.

However, forecasters predict relief in coming days.

The Royal Meteorological Institute in Belgium said temperatures Thursday and Friday should be only in the high 70s.

Meteo France said temperatures throughout France were expected to drop by midweek -- although they would remain well above average. Forecasters were predicting a high of 84 for Thursday in the French capital.

The German Weather Service forecast falling temperatures over the next two days with Wednesday's expected arrival of a cold front from Scandinavia.