Yes, but also no. When you put it like that, it sounds like switching to a 100% renewable electricity tariff counts for nothing, because there's no way for me to avoid gas (and even coal) being burnt to generate the electricity that goes into the grid and that I use to charge my electric car and to power my heat pump (when eventually VW delivers the ID.3 and when I get the heat pump fitted...).
Yet I am reasoning that a 100% renewable electricity tariff (backed by Ofgem's REGO certificates) is just as good as (or better than) fitting solar panels to my roof, with the goal of "ensuring" that my EV and ASHP are 100% powered by renewable electricity. (For the sake of argument, let's ignore cost.)
How about this way of thinking about it. Suppose that I bought 10 solar panels and a small wind turbine that happened to match (for the sake of argument) 100% of my house's energy needs. Then, consider 2 scenarios:
- I fit the 10 solar panels to my house's roof and I put up the small wind turbine on my rear garden, and connect the cables to my consumer unit. (Ignore planning permission and neighbours' complaints...)
- Alternatively, instead of attaching them to my house, I rent a small piece of farmland 100 miles away and I fit the panels and turbine to the ground over there, and I connect them to the national grid over there. I also fit an electricity meter that measures how much energy my panels and my small turbine supplied to the grid, and every year, Ofgem issues some REGO certificates to me, matching the amount I produced on my small piece of rented farmland. Then I sell those certificates to some supplier willing to buy them, let's call it Bulb (coincidentally my current energy supplier).
Now, replace my hypothetical solar panels and wind turbine on my hypothetical piece of farmland 100 miles away by anyone else's wind farm / solar farm / tidal generators who are issued REGO certificates that they happened to sell to Bulb. How's that any different? Just because I am not the owner of the solar panels and turbine and they are not attached directly to my roof and garden, doesn't really change my ability to claim that my EV and ASHP are powered by 100% renewable energy as long as the money I paid to my supplier (electricity bill, 100% renewable energy tariff) was used by the supplier to buy the REGO certificates from some else's wind farm / solar farm / tidal generators, in a quantity matching my electricity usage.
This post sounds like I am trying to convince you, but I am equally trying to convince myself. The good news is, I think I've managed to convince myself.