Does Technology Save Us?

I think that technology is necessary for us to improve the environment as many people believe, because technology is helpful for the environmetal problem. Technology reduces waste and negative influence on the environment as it can be seen hybrid cars and buses, for instance. However, I think that technology is not the only and a perfect solution of the environmental issue.
One reason is, technology might be efficient but I assume we are not really sure how those technologies are effective to the environmental issue. If everyone uses eco-friendly technologies and products, does it mean we do not have to care or change how much or how many products or stuff we consume? For example, if I bought a hybrid car, does it mean I can choose to drive more instead of walking or using bus and metro? I think it doesn't. Even we could reduce costs and material to produce something, it won't save the environment if our consumption keep increasing.
Another reason is, no matter how technology is helpful for the environment, it usually costs expensive to develop and use. If technology was expensive, not everyone can afford it. Especially developing countries would still remain being left behind instead of people living more efficient and improving the environment. If people don't use the technology (or only rich people are using eno-friendly technologies), it'll be meaningless.
Again, I think that technology is helpful but we just cannot rely on technology to save the environment.