Is there a finite amount of renewable electricity and gas?

I gather that Bulb has managed to increase its customer base from 100,000 at the start of 2017 to 250,000 by the end of 2017. Well done! It begs a question however. Bulb supplies 100% of its electricity from renewable supplies. Given that (presumably) there is a finite amount of renewable electricity (and indeed gas) available, and given the large increase in its customer base, will Bulb still be able to provide its customers with 100% electricity (and 10% of its gas supplies) from renewables?

Hi @PeterS, definitely something to think about.
If I remember correctly, the 100k customers date was at the start of August and the 250k figure was around the middle of December, so growth was even faster than you suggested!

At present, as we’re always producing more than 20% of the UK’s power from renewable sources (normally more like 25% and it’s rising all the time) and Bulb only supply close to 1% of UK properties, even with the other renewable suppliers we should be OK for electricity for a while.

In terms of biogas, a figure was given on here before of something like 250k houses could be supplied with 100% biomethane, which would be 2.5M customers at Bulb’s 10% figure presuming they can buy it all.
Unless the generation figure goes up significantly in the future, it may become more and more difficult for them to buy the biomethane required, but they’ve probably got a few years to go before they reach 2M customers.

@PeterS There is a growing capacity for the renewable capacity too, so everything @mowcius said is correct but there is still expansion in renewable capacity all the time.

Renewable gas is a rapidly growing industry too as more processes are beginning to utilise their waste products to produce renewable gas as a useful by-product.

The renewable certificates are very under utilised, with such a small number of domestic/businesses on a renewable tariff, so there is still capacity for us to grow with a 100% tariff.

We won’t ever use anything other than renewable energy and as much renewable gas is feasible at the time. It’s something that we’re all very passionate about keeping in place.

@“Rob at Bulb”, do you know what the rate of expansion in the biogas industry is?
I suspect it’s nothing like the 250% increase Bulb had in the last 4 months…

Obviously it’s likely that Bulb’s growth won’t continue at this rapid pace forever but if it did, you’d presumably face issues around 2020?

Do you have a graph of the number of Bulb customers? It would be fascinating to see member numbers over time. Presumably you’re at around 270k now?

We should also point out that our grand master plan to save the world is to increase the demand for renewable energy so that more people invest in it in future. The more people join Bulb, the more green power we buy, so the more people build green power plants. As we grow, basic economics should encourage growth in generation too :slight_smile:

Green gas may or may not grow at the same rate as us, but we’re unlikely to keep growth at 250% every 6 months :slight_smile: I think getting so big that there isn’t enough green energy it would be a lovely problem for us to have. We would always buy green power though. If there wasn’t enough green power for us to grow, we’d pause our marketing and have a rethink.

It’s difficult to get a good figure on the growth of the biogas industry. This article says it increased by 30% in a year, while this article says 18% for the same period. And it’s difficult to know when an article is talking about biogas pumped into the gas grid, versus biogas burned for electricity. Either way, it’s on the up!

I can’t share the graph you’re hoping for. You’ll be able to imagine the shape I’m sure, but beyond the numbers that we periodically announce, our member numbers are commercially sensitive info which we want to keep quite close to our chest.

@“Will at Bulb”, fair enough on the graph.

Are there any historically announced figures that you can provide that I’m not aware of?

I know when 100k, 200k and 250k were (all announced by Bulb, 250k more quietly in a comment on the forum), but I don’t know before then.

@mowcius, I don’t have the exact numbers and dates that we published them, but here you go:

0 customers, 27th August 2015 (day we launched)
34,000ish, Aprilish 2017 (We told members which number they were in our 100k announcement, so some journalists reverse engineered their numbers and published them)
100,000ish, 27th August 2017 (We celebrated 100k on our birthday)
200,000, Novemberish 2017 (We gave double referral rewards in celebration of 200k)
250,000, Decemberish 2017 (We stated this in a BEIS Committee panel)

:mrgreen: I’m guessing the steeper slope at the bottom is wrong but it’s all fuzzy and inaccurate anyway.

I also saw Hayden mention 300,000 in a feature on BBC news the other day so it’s safe to assume growth hasnt stalled yet :slight_smile:

I also saw Hayden mention 300,000 in a feature on BBC news the other day so it's safe to assume growth hasnt stalled yet :)
Yup; the vid is only a minute: http://www.bbc.co.uk/news/av/business-42821700/when-you-grow-quickly-it-can-be-challenging

@alex, it sounds like they’re working on slowing it down though.

Previously it had been mentioned that removing themselves from price comparison sites should slow growth so that may be what has been done.
I don’t believe a figure has been given regarding the percentage of customers generated from those sites, but back around 170k customers a figure of just 17% was given for referrals, so comparison sites produced the largest amount of growth back then at least.

@AndrewC, I hadn’t seen that, thanks for the link.

Their status screen shown in the video nicely sums up why phoning is always best…

Average of 11.5 hours on email still beats the pants off most companies though.