It seems like plotly gauge charts are not compatible with subplot because I end up with two gauge charts on top of each other.
library(plotly)
fig1 <- plot_ly(
  domain = list(x = c(0, 1), y = c(0, 1)),
  value = 270,
  title = list(text = "Speed"),
  type = "indicator",
  mode = "gauge+number") 
fig1 <- fig1 %>%
  layout(margin = list(l=20,r=30))
fig1
fig2 <- plot_ly(
  domain = list(x = c(0, 1), y = c(0, 1)),
  value = 50,
  title = list(text = "Speed"),
  type = "indicator",
  mode = "gauge+number") 
fig2 <- fig2 %>%
  layout(margin = list(l=20,r=30))
fig2
fig <- subplot(fig1,fig2)
fig
