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Yes, but you will measure the voltage and current independently, therefore you will be able to calculate only apparent power (VA), not real power (W). See Building Blocks.

I presume you cannot access voltage and current from the same place - not necessarily at the meter?

Not possible as the location of the meter is outside and no where near a power source. 

I only have access to the active wire from the meter to the fuse box. The PV active is connected to the fuse box and I cannot get to it either.  I am currently collecting the pv output directly from the SMA inverter.

I just need a ct value that can provide me with a positive and negative value.

"I just need a ct value that can provide me with a positive and negative value."

By that, do you mean you need to know the direction of power flow? If that's the case, you absolutely need to measure voltage and current in one place using the emonLib real power calculations or an equivalent. If you measure voltage and current independently, you do not know the timing relationship between them and you cannot know their relative phase, which is what tells you the direction of power flow.

What prevents you from installing a power outlet at or within reach of the fuse box? Can you get a thin (3 mm diameter) cable from the fuse box to a place where there is a power outlet?

Here in Australia most fuse boxes are installed on an external wall.  As for a power point at the fuse box, unlikely to happen either. 

To run a 3mm cable from the fuse box to a suitable power source would require something in the order of a 10mtr run of cable.  The local power authority here is very particular about who plays in the fuse box.  This is why I have asked the question. 

The guy who installed my upgrade did not do me any favors when he installed the equipment. I cannot get access to just the house active leads either.

I can think of a way, but it'll require some construction and a fairly big battery to get a decent life:

You need a capacitive pickup to detect the voltage - it's been discussed here before, try a search, and a normal emonTx slightly modified to accept the different voltage input. As far as I know, all the parts have worked individually, but never been put together as a system. If that appeals, let me know.

Robert.
More than happy to try and build something to give me a result.
Any assistance is appreciated .

Mark

As for a power point at the fuse box, unlikely to happen either. 

That's a fairly easy problem to solve.  I've got a tame sparkie who was out doing other work and added the outdoor GPO pretty much for the price of the weatherproof outlet.  Going with the double means I've now got a spare out there for other use.  I've also seen quite a few Australian fuse boxes with a low profile outlet installed right on the meter board inside the box.

If you don't have a cooperative sparkie, then take a look here for starters.
It assumed that the ADC input was using the internal reference of 1.1 V, not AVcc (3.3 V) as is standard. (That's the reason for the input being biased to around ½ V, not half the supply voltage.) It's worth reading all of that thread.

The op.amp needs to be single rail, with rail-rail input, and low supply current (for best battery life). If you're using the "discrete samples" sketch, you could feed the op.amp from the temperature sensor supply and switch it on only while you're sampling.