Bridge Power!

When you ask someone what they think of when someone mentions renewable energy the most common answer is solar power or wind power. The problem with these two sources is that they are annoyingly unpredictable. Solar power only works for half the day when the sun is out and even during the day, certain conditions such as clouds and rain can restrict the amount of energy collected. Wind turbines obviously use the wind to generate electricity but as everyone knows, the wind is arguably one of the most unpredictable things created by Mother Nature. People have started to realize this and its resulted in wind power efforts to be the lowest they have been in the last four years.

Tidal power on the other hand, is relatively predictable and since our planet’s surface is 70% ocean there is an abundance of real estate available. If all the world’s oceans were set up with some type of tidal power harnesser, in five days enough energy would have been generated to power the entire United States of America for a year!! I think that one fact tells us the answers to all our energy problems. Obviously I know that we can’t hook up the entire ocean because of problems such as not having an efficient way to transport electricity long distances and extreme temperatures and pressures. The most popular way to capture tidal power is to plant underwater windmills everywhere. The problem with this is the that most of the underwater currents just kind of slip around the blades of the windmill which results in only 35% of the energy in the currents to harnessed.

A Canadian company called Blue Energy has created a turbine system that is installed underneath bridges. The system stacks hundreds of seven-megawatt turbines on top of each other so that there is no free space for the water to flow except through the turbines. This creates a slight damming effect that forces the water through but it is still slow enough to be safe for fish. This system results in each turbine generating 4 times as much power that a standard “underwater windmill” turbine makes. IF the Golden Gate Bridge was to be outfitted with this system it would create enough electricity to power the ENTIRE CIRTY OF SAN FRANSICO! That’s the equivalent of 2,000 megawatts!

Another thing this system has over other dam systems is that to maintain the turbines a permanent crane on rails is attached to the road deck where individual turbines can be brought up so that they can be periodically serviced. Other systems similar to this, divers or for larger systems, specialized submarines must go and service the turbines underwater.