I mean literally today anything I want is available to me 24/7.

I can buy anything anytime.

In fact 79% of Americans shop online.

This happens when they're laying in bed, while they're out with friends having a drink.

It turns out actually one in five of us shop online while we're using the bathroom.

All this stuff we're buying sort of magically appears on our doorstep.

But what effect does all this shopping have on the planet?

Delivery services ship a lot more packages now because of online shopping.

Since 2009 US Postal Service deliveries increased by 65%.

And during the holidays, UPS deliveries have increased by 260 million packages since 2010.

Now for the most part, if you compare online shopping with driving to the store, online shopping has a smaller carbon footprint.

But there's a catch.

It's only better for the environment if you don't get rushed delivery.

Most of us, including me, are choosing faster delivery like two day shipping because most of the time it's free.

Why wouldn't we want it right away?

But it isn't just a time difference, it's an environmental difference.

All these faster deliveries means way more trucks on the road and that's causing more greenhouse gases.

And that means more global warming.

When we choose two-day shipping, deliveries often come in multiple packages.

Let's say I buy some dish soap and a pair of socks.

The shipping warehouse near me might be out of dish soap, so they fly some in from another state.

Meanwhile, those socks, they're getting sent to me on a separate truck.

Also, the company is trying to get it to me quickly, so trucks are often sent out only half fullㄡ

If there was more flexibility in timing, they could fill them up all the way.

If you know you have five-day delivery window, you can wait from all the products to come in from different sources, consolidate the shipment, and send it.

And now you can wait for many customers' orders to come in and consolidate that into, let's say, a full truckload.

This is Miguel Jaller.

He studies sustainable transportation at the University of California, Davis.

By picking the longer delivery window, I'm giving the company more time to find the most efficient way to get a product to me.

Another problem is with returns.

So one of the things that companies made is offering this reliable and fast and almost free return option.

So now as a customer, I can actually try the product, even if I don't have any store to go to,

because if I don't like it or it doesn't fit, I can actually return it at no cost.

So like with buying clothes, if I shop online and pick the 'try before you buy' option,

it would be the same as saying a delivery truck is driving back and forth just to find me the right stuff.

So what are companies trying to do?

When you think of the future of online shipping, you might imagine drones and driverless cars.

But today's solutions are more about keeping traffic moving along, like with wifi traffic lights

that let truckers know ahead of time when the light will turn red.

This cuts down on idling at the light and wasting fuel.

We're now starting to transmit the timing of those traffic lights,

in anticipation for that, they might want to speed up a little bit or slow down or do these certain little velocity changes

so that they increase their chances of getting through that light.

This is Matt Barth at the University of California, Riverside.

He's looking at ways that trucks can reduce their transit footprint.

You can essentially smooth out your patterns of travel.

And when you smooth out your travel patterns, you get those fuel-economy benefits.

Cities like San Jose and Las Vegas are already testing out this traffic light technology.

You can save 15 to 20 percent fuel just by doing those type of activities.

And on the highway, trucks are actually now starting to talk to each other -- it's called truck platooning.

You can think of it like cruise control except its transmitting the truck's speed to the other vehicles following behind.

This lets all the trucks drive in unison at the same speed close behind each other.

What they're doing is trying to reduce the drag.

The narrow gaps they create between each other shields the trucks that are following from wind resistance.

And so there's been a number of experiments worldwide that have shown, you know,

you can get 10 to 15, 20 percent energy savings, fuel savings by doing that type of platooning.

Now delivery companies have been tackling fuel use and emissions for decades.

Take UPS.

Since the 1970s they've encouraged drivers to eliminate left hand turns, reducing their emissions by 100,000 metric tons.

That's like taking 21,000 cars off the road.

So there are ways companies can shrink their carbon footprint, but what if they were better about changing customer behavior –

like getting all of us to be conscious about how we shop online?

I've always picked that 2 day option because to be honest never really thought about it,

but what if companies offered a green option?

So if you just check a box they would just ship stuff to you in the most energy efficient way possible.

Sure, maybe it takes a little longer, but that's something I'd actually be willing to do.

I mean every now and again, I agree,I might need something right away.

But I probably don't need overnight delivery of socks to my front door.

You probably do a lot of your online shopping with your smartphone.

Well watch our other episodes to see what kind of impact these devices have on our planet.